Answer:4
Step-by-step explanation:
distribute 1/2 into x-8 and distribute 2 into 1/8x-1 on other side
1/2x-4+1=1/4x-2
combine like terms
1/4x=1
multiply both sides by 4 to solve x
x=4
A circle is centered at (−5, 8) and has a radius of 7. Which of the following is the equation of this circle? Group of answer choices (x + 5)2 + (x − 8)2 = 49 (x + 5)2 + (x − 8)2 = 7 (x − 5)2 + (x + 8)2 = 7 (x − 5)2 + (x + 8)2 = 49
The equation of the circle centered at (−5, 8) and having a radius of 7 is (x + 5)² + (y - 8)² = 49.
What is the equation of the circle centered at (−5, 8) and has a radius of 7?The standard form of the equation of a circle is expressed as;
x² + y² = r²
The horizontal (h) and vertical (k) translations represents the center of the circle.
Hence;
(x - h)² + (y - k)² = r²
Given the data in the question;
Center of the circle: (−5, 8)
h = -5k = 8r = 7Equation of the circle = ?Now, plug the values of h, k and r into the equation above and simplify,
(x - h)² + (y - k)² = r²
( x - (-5) )² + ( y - 8 )² = 7²
(x + 5)² + (y - 8)² = 49
Therefore, the equation of the circle is (x + 5)² + (y - 8)² = 49.
Hence, option A is the correct answer.
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Tessa has a new beaded necklace. 18 out of the 45 beads on the necklace are blue. What
percentage of beads on Tessa's necklace are blue?
Answer: 40%
Step-by-step explanation: 18/45 = x/100
divide 100 by 45 and you get 2.22 repeating.
multiply 2.22 by 18 and you get 40%
Evaluate the expression and enter your answer in the box below.
|42|
Answer:
42
Step-by-step explanation:
because the distance between 42 and zero is 42
(03.06 MC)
Aurora is planning to participate in an event at her school's field day that requires her to complete tasks at various stations in the fastest time possible. To prepare for the event, she is practicing and keeping track of her time to complete each station.
The x-coordinate is the station number, and the y-coordinate is the time in minutes since the start of the race that she completed the task.
(1, 3), (2, 6), (3, 12), (4, 24)
Part A: Is this data modeling an arithmetic sequence or a geometric sequence? Explain your answer. (2 points)
Part B: Use a recursive formula to determine the time she will complete station 5. Show your work. (4 points)
Part C: Use an explicit formula to find the time she will complete the 9th station. Show your work. (4 points)
A) The data models a geometric sequence
B) Using a recursive formula, the time she will complete station 5 is; 2
C) Using a explicit formula, the time she will complete station 9 is; 512
How to find the Recursive Formula?A) From the given coordinates (1, 3), (2, 6), (3, 12), (4, 24), we can say that when x increases by 1, y is multiplied by 2. Thus, as the quotient between consecutive terms is the same, the data depicts a geometric sequence.
B) The recursive formula for a geometric sequence with common ratio r and first term a₁ is given by the formula:
f(n) = a₁(r)ⁿ⁻¹
Since a₁ = 2 and r = 1, then we have;
f(1) = 2(1)¹⁻¹
f(1) = 2
f(5) = 2
C) The explicit formula from the calculations above will be;
aₙ = 2ⁿ
Thus;
a₉ = 2⁹
a₉ = 512
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samples of size 5 are selected from a manufacturing process. the mean of the sample ranges is 0.50. what is the estimate of the standard deviation of the population? (round your answer to 3 decimal places.)
The estimate value of the standard deviation of the population ( manufacturing process) is 0.125..
The standard deviations is estimated to be one fourth of the sample range (as most of data values are within two standard deviations of the mean).
We have given that,
A sample of manufacturing process.
Sample size, n = 5
Mean of sample ranges = 0.50
we have to calculate the estimate of standard deviations of population.
thus , we estimate the standard deviations as fourth of the mean of the sample ranges is
S = Mean of sample ranges/4
=> S = 0.50/4
=> S = 0.125
Hence, the standard deviation of the population is estimated as 0.125..
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Find the slope of the line through (7,-6),perpendicular to y=4x+2
Answer:
4y+x+17=0Step-by-step explanation:
y=4x+2
For a point to be perpendicular to a line
then the product of the two gradients must be negative one (I.e, m1×m2=-1)
where m1= 4
m2=-(1/m1)
m2=-1/4
point (7,-6)
x1=7 y1=-6
from the general equation of a line
y-y1=m(x-x1)
y-(-6)=-1/4(x-7)
y+6=-1/4(x-7)
y+6=-1/4x+7/4
y+1/4x=(7/4)-6
y+1/4x=-17/4
y+1/4x+17/4=0
4y+x+17=0
given f (x) = 2x + 7 describe how the value of k affects the slope and y intercept of the graph of g compared to the graph of f 9 (x) = (2x +7) - 6
The slope of both functions remains the same, there is no effect of the value of k on a slope.
What is a slope?Slope or the gradient is the number or the ratio which determines the direction or the steepness of the line.
Change in the value of y-intercept. For f(x) y-intercept is 5 and for g(x) y-intercept is 2.
The given functions are :
f(x) = 2x + 5
g(x) = ( 2x + 5) -3
From the graph of both functions,
Let us consider two pairs of coordinates to find the slope,
For f(x)
(0,5) and ( -2, 1)
The slope of f(x)
m= ( 1- 5) / (-2 -0)
m= 2
For g(x) at (0,2) and (-1, 0) slope of g(x),
m = ( 0-2) / (-1-0)
m = 2
The slope remains unaffected.
y-intercept of f(x) , put x = 0
⇒ y = 5
y-intercept of g(x) , put x = 0
y =(0+ 5) -3
y = 2
Change in the value of y-intercept due to the value of k = -3.
Therefore, for the given function f(x) = 2x + 5 and g(x) = ( 2x + 5) -3, the effects of the value of k on slope and y-intercept are as follows:
The slope of both functions remains the same, there is no effect of the value of k on a slope.
Change in the value of y-intercept. For f(x) y-intercept is 5 and for g(x) y-intercept is 2.
The graph is attached.
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Solve the equation for y.
x = 4y-2
y=
Answer:
Step-by-step explanation:
Solve each inequality. Use the number line provided to test intervals.
Thank you!! :)
Answer: x ∈ {-0.5, -5, -12.5}
Step-by-step explanation: To solve the inequality 2x³ + 21x² + 60x + 25 > 0, we first need to find the values of x that make the inequality true. We can do this by setting the expression equal to 0 and solving for x.
We can start by factoring the expression to make it easier to solve. Notice that 2x³ + 21x² + 60x + 25 is a polynomial with a leading coefficient of 2 and a constant term of 25. This means that it has the form (x + a)(x + b)(x + c), where a, b, and c are constants.
We can start by factoring out the common factor of 2x from the first two terms: 2x³ + 21x² + 60x + 25 = 2x(x² + 10.5x + 12.5). Now we can see that the expression has the form (x + a)(x + b)(x + c), where a = 0.5, b = 5, and c = 12.5.
So, we can rewrite the expression as (x + 0.5)(x + 5)(x + 12.5) = 0. Now we can solve for x by setting each factor equal to 0 and solving for x:
x + 0.5 = 0 => x = -0.5
x + 5 = 0 => x = -5
x + 12.5 = 0 => x = -12.5
Therefore, the values of x that make the inequality true are x = -0.5, x = -5, and x = -12.5.
Now we need to determine which of these values make the inequality 2x³ + 21x² + 60x + 25 > 0 true. To do this, we can substitute each of the values of x into the inequality and see which ones make the inequality true.
When x = -0.5, the inequality becomes 2(-0.5)³ + 21(-0.5)² + 60(-0.5) + 25 > 0, which simplifies to -0.5 + 5.25 - 15 + 25 > 0. This is true, because the left-hand side is 29 > 0.
When x = -5, the inequality becomes 2(-5)³ + 21(-5)² + 60(-5) + 25 > 0, which simplifies to -125 + 525 - 300 + 25 > 0. This is also true, because the left-hand side is 225 > 0.
When x = -12.5, the inequality becomes 2(-12.5)³ + 21(-12.5)² + 60(-12.5) + 25 > 0, which simplifies to -391.25 + 1181.25 - 750 + 25 > 0. This is also true, because the left-hand side is 1147.5 > 0.
Therefore, the solution to the inequality is x ∈ {-0.5, -5, -12.5}. This means that the values of x that make the inequality true are x = -0.5, x = -5, and x = -12.5. The inequality is satisfied when x is any of these values.
I need help with this asap please
Answer: C
Step-by-step explanation:
-2 and 2 add up to 0
Answer:
c
Step-by-step explanation:
-2 + 2 =0
y= 3x + -2
y= x -4
HELP ME
Answer:
y=-3x+2 y=-x-4
Step-by-step explanation:
How do i do this? The real answer is supposed to be 1/16 but I don't know how to get there.
a) The student's work is False and the strategy is incorrect as the fraction should be 1/16
b) The fraction 1/16 as decimal is 0.0625
What is an Equation?
Equations are mathematical statements with two algebraic expressions flanking the equals (=) sign on either side.
It demonstrates the equality of the relationship between the expressions printed on the left and right sides.
Coefficients, variables, operators, constants, terms, expressions, and the equal to sign are some of the components of an equation. The "=" sign and terms on both sides must always be present when writing an equation.
Given data ,
Let the number be = A
Now the value of A is A = 6 1/4 %
The value of A = 6.25 %
Now , the value of 6.25 % = 6.25 / 100
The fractional form can be substituted by dividing the numerator and denominator by 25 , we get
A = 6.25 / 100
A = ( ( 6.25 ) / 25 ) / ( 100 / 25 )
A = ( 0.25 ) / 4
The value of A = 0.25 / 4
The value of A = 0.0625
And it can be represented in the fractional form as
A = 0.25 / 4
The value of 0.25 = 1/4
Substituting the value of 0.25 in the equation , we get
A = ( 1/4 ) / 4
A = 1/16
Therefore , the value of A = 1/16
b)
The decimal from of the number 1/16 is 0.0625
The mistake the student did was while dividing the number by 100 to convert the percentage , the student evaluated the number 625 instead of 6.25 , so after avoiding the error , we get the fraction as 1/16
The decimal from of the number 1/16 is 0.0625
Hence ,
a) The student's work is False and the strategy is incorrect as the fraction should be 1/16
b) The fraction 1/16 as decimal is 0.0625
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In someone infected with measles, the virus level N (measured in number of infected cells per mL of blood plasma) reaches a peak density at about t = 12 days (when a rash appears) and then decreases fairly rapidly as a result of immune response. The area under the graph of N(t) from t = 0 to t = 12 (as shown in the figure) is equal to the total amount of infection needed to develop symptoms (measured in density of infected cells x time). The function N has been modeled by the function f(t) = -t(t - 21)(t + 1). Use this model with six subintervals and their midpoints to estimate the total amount of infection needed to develop symptoms of measles.
The total amount of infection needed to develop symptoms of measles is 7840
Consider the model,
N(t)= f(t)=-t(t-21)(t+1).
The area of the graph of N(t) from t=0 to t = 12 is,
N(t)dt
Use six subintervals and their midpoints to estimate the above as follows:
Here, a=0,b=12, n=6
The length of each subinterval is,
h= b-a/n = 12-0/6
=2
So, the midpoints of each subinterval are 1, 3, 5, 7, 9, and 11.
Use Midpoint Rule,
A = [N(t)dt]
= At[ƒ (1) + ƒ (3) + ƒ (5) +ƒ(7)+ƒ(9)+ƒ(11)] =2[40+216+480+784+1080+1320]
= 7840
Thus, the total amount of infection needed to develop symptoms of measles is 7840.
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What is 35.7 divided by 0.07
Answer:
510
Step-by-step explanation:
Answer: The answer is 510
Step-by-step explanation:
35.7/0.07 = 510
A common guideline for constructing a 95% confidence interval is to place upper and lower bounds one standard error on either side of the mean.
True
False
False. Because a 95% confidence interval is two standard errors on either side of the mean.
What is a 95% confidence interval?
If 100 separate samples were taken and a 95% confidence interval was calculated for each sample, then around 95 of the 100 confidence intervals would contain the actual mean value (), according to the definition of a 95% confidence interval.
For a 95% confidence interval, the value lies within 2 standard deviations of the normal distribution.
For upper and lower bounds one standard error on either side of the mean is 68%.
So, the 95% confidence interval is two standard errors on either side of the mean.
Hence, the given statement is False.
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Use the probability distribution and histogram found here to select the correct probability for each statement.
The probability that a randomly selected student has fewer than 4 siblings is P(X<✓4)=0. 89
The probability that a randomly selected student has at least 5 siblings is P(X≥ ✓ 5
The probability that a randomly selected student is not an only child is P(X # 0) = 0. 75
☐
4
=✓0. 04✓
The probabilities are given as follows:
Fewer than 4 siblings: P(X < 4) = 0.737.At least 5 siblings: P(X >= 5) = 0.111.Not an only child: P(X > 1) = 0.734.How to obtain the probabilities?The probabilities are called identifying the desired outcomes from the distribution of the number of children per parent.
Hence the probability of fewer than 4 siblings is of:
P(X < 4) = P(X = 1) + P(X = 2) + P(X = 3) = 0.266 + 0.322 + 0.149 = 0.737.
The probability of at least 5 siblings is of:
P(X >= 5) = P(X = 5) + P(X = 6) + P(X > 6) = 0.059 + 0.032 + 0.02 = 0.111.
The probability that the student is not an only child is given as follows:
P(X > 1) = 1 - P(X = 1) = 1 - 0.266 = 0.734.
Missing InformationThe distribution is given as follows:
P(X = 1) = 0.266.P(X = 2) = 0.322.P(X = 3) = 0.149.P(X = 4) = 0.152.P(X = 5) = 0.059.P(X = 6) = 0.032.P(X > 6) = 0.02.More can be learned about probabilities at https://brainly.com/question/14398287
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a food server examines the amount of money earned in tips after working an 8-hour shift. the server has a total of $95 in denominations of $1, $5, $10, and $20 bills. the total number of paper bills is 26. the number of $5 bills is 4 times the number of $10 bills, and the number of $1 bills is 1 less than twice the number of $5 bills. write a system of linear equations to represent the situation. (assume x
The solution to the system equation is (x, y, z, w) = (23, 12, 3, 1).
What is equation?
An equation could be a formula that expresses the equality of 2 expressions, by connecting them with the sign =
Main body:
Here is a system of linear equations that represents the situation.
x +5y +10z +20w = 133 . . . total amount earned
x +y +z +w = 39 . . . . . . . . . total number of bills
y = 4z . . . . . . . . . . . . . . . . . . the number of 5s is 4 times the number of 10s
x = 2y -1 . . . . . . . . . . . . . . . . the number of 1s is 1 less than twice the number of 5s
_____
We can substitute for x and z in the first two equations:
... (2y-1) +5y +10(y/4) +20w = 133
... (2y-1) +y +(y/4) +w = 39
These simplify to
... 9.5y +20w = 134
... 3.25y +w = 40
Solving by your favorite method, you get
... y = 12
... w = 1
So the other values can be found to be
... x = 2·12 -1 = 23
... z = 12/4 = 3
hence ,The solution to the system is (x, y, z, w) = (23, 12, 3, 1).
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the polynomial that represents the volume of the box is 6x3 32x2 2x - 40. find the volume of the box if x is 4 inches.
the polynomial that represents the volume of the box is is 6x^3 +5x^2 -3x-2
V=lwh
l=x+1
w=2x+1
h=3x-2
V=(x+1)(2x+1)(3x-2)
V=(x*2x+x*1+1*2x+1*1)(3x-2)
V=(2x²+x+2x+1)(3x-2)
V=(2x²+3x+1)(3x-2)
V=2x²*3x+2x²*(-2)+3x*3x+3x*(-2)+1*3x+1*(-2)
V=6x³-4x²+9x²-6x+3x-2
V=6x³+5x²-3x-2
complete question is
Find the volume of the box. Use the formula V = lwh.
Rectangular box with sides x plus 1, 2x plus 1, and 3x minus 2.
6x3 – 2
6x3+ x – 2
6x3 – 13x2 – 3x – 2
6x3 + 5x2 – 3x – 2
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Please answer. Question below!
Answer:
Solution = (5, 2)
Step-by-step explanation:
Step 1: Solve for y in 9x + 2y = 49
1. 9x + 2y = 49 → 2y = -9x + 49 → y = -4.5x + 24.5
Step 2: Substitute -4.5x + 24.5 for y in -3x + 5y = -5
2. -3x + 5(-4.5x + 24.5) = -5
Step 3: Solve for x
3. -3x - 22.5x + 122.5 = -5 → -25.5x + 122.5 = -5 → -25.5x = -127.5 → x = 5
Step 4: Substitute 5 for x in -3x + 5y = -5
4. -3(5) + 5y = -5 → -15 + 5y = -5 → 5y = 10 → y = 2
Hope this helps :)
The sum of two numbers is 19. The second number is 2 more than twice the first number.
Answer: 5[tex]\frac{2}{3}[/tex]
Step-by-step explanation:
19=(x+(2x+2))
Subtract 2 from each side
17=x+2x
17=3x
Divide each side by 3
[tex]\frac{17}{3}[/tex] = x
5 [tex]\frac{2}{3}[/tex] = x
the mean of five positive integers is 1.5 times their median. four of the integers are 8, 18, 36 and 62, and the largest integer is not 62. what is the largest integer?
The largest number of the five positive integers is 146.
Mean:
The mean is the mathematical average of a set of two or more numbers. The arithmetic mean and the geometric mean are two types of mean that can be calculated. The formula for calculating the arithmetic mean is to add up the numbers in a set and divide by the total quantity of numbers in the set.
Median:
The median is the middle value in a set of data. First, organize and order the data from smallest to largest. To find the midpoint value, divide the number of observations by two. If there are an odd number of observations, round that number up, and the value in that position is the median.
Here we have to find the largest integer.
Data given:
Four of the five integers are 8, 18, 36, and 62.
It is given that mean of five numbers 1.5 times their median.
mean = (8+18+36+62 + x)/5
median = 36
mean = 1.5 × median
(124 + x) / 5 = 1.5 × 36
124 + x = 5 × 54
x = 270 - 124
= 146
Therefore we get the largest number as 146.
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Step by step please help asap !!!!!!!
Answer:
3,31
Step-by-step explanation:
i dont got steps for this but i think thats the right answer
Jack has 18 fewer points than Aria, who has x points.
Answer: x-18
Step-by-step explanation:
So far, you proved that one pair of parallel sides in a parallelogram
must be congruent. Add to your proof to prove that both pairs of
parallel sides in a parallelogram must be congruent.
Geometry
Both the pairs of opposite sides in a parallelogram are parallel and congruent.
According to the question,
We've proved that one pair of sides in parallelogram must be congruent
Let ABCD is a parallelogram ,
We know that AB // CD
Here, AC is transversal for the parallel lines AB and CD
So, ∠BAC = ∠DCA (Using interior angle property) --------(1)
Similarly , We also know that BC // AD
=> ∠BCA = ∠DAC -----------(2)
Now , In ΔABC and ΔADC,
∠BAC = ∠DCA from (1) AC is common side∠BCA = ∠DAC from (2)Therefore , ΔABC ≅ ΔADC (as per ASA congruence rule)
Therefore , AB = CD and BC=AD (Corresponding sides of congruent triangles are equal)
Hence , Both the pairs of opposite sides in a parallelogram are parallel and congruent.
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why are we able to solve the wason task with examples (whether one is 21 and drinking alcohol) rather than letters and numbers? group of answer choices
The Wason selection test measures a person's ability to recognize information that challenges a certain hypothesis, in this case, a type of conditional hypothesis. if P, then Q.
Given,
Wason's Card;
A popular tool for studying problem resolution that was developed in 1966 by English psychologist Peter C(athcart) Wason (1924–2003). The uppermost faces of the four cards, which are arranged on a table, display the letters and numerals E, K, 4, and 7.
What is demonstrated by the Wason selection task?
As a result, the Wason selection test gauges how well people can spot evidence that refutes a certain hypothesis, in this case, a conditional hypothesis of the type. P, then Q if.
For example;-
The majority of people have no trouble choosing the proper cards ("16" and "drinking beer") if the rule is "If you are drinking alcohol, then you must be over 18" and the cards contain an age and beverage on one side, respectively.
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"A scientist uses a submarine to study ocean life. She begins at sea level, which is an elevation of 0 feet. She travels straight down for 90 seconds at a speed of 3.5 feet per second. She then travels directly up for 30 seconds at a speed of 2.2 feet per second. After this 120 second period, how much time, in seconds, will it take for the scientist to travel back to sea level at the submarine's maximum speed of 4.8 feet per second? Round your answer to the nearest tenth of a second." I need this done soon, please help.
It will take 51.9 seconds to return to sea level.
What is speed?The rate of change of position of an object in any direction. Speed is measured as the ratio of distance to the time in which the distance was covered.
Using the speed - distance relationship, the time taken for the scientist to travel back to sea level would be 51.9 seconds
Distance = Speed × time
First travel :
Distance covered = 90 × 3.5 = 315 feet
Second travel :
Distance covered = 30 × 2.2 = 66 feet
Net change in position from sea level :
(315 - 66) feet = 249 feet
Maximum speed = 4.8 feet per second
Time taken = Distance / speed
Time taken = 249 ÷ 4.8 = 51.875 seconds
Hence, it will take 51.9 seconds to return to sea level.
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A cardboard carrying box has the dimensions shown below. How many square inches of cardboard are needed to make the box?
a person casts a shadow that aligns with a shadow of a tree. the person is 5.5 feet tall and casts a shadow 8.25 feet long. the trees shadow measures 22.5 feet long
Part A: write and equation you can use to find the trees hight.
Part B: How tall is the tree? How far is the person standing from the tree?
An equation that can be used to determine the tree's height is 22.5/8.25 = x/5.5.
The height of this tree is equal to 15 feet.
The distance of this person from the tree is equal to 14.25 feet.
What are the properties of similar triangles?In Geometry, two (2) triangles are similar when the ratio of their corresponding sides are equal in magnitude and their corresponding angles are congruent.
Additionally, two (2) geometric figures are considered to be congruent only when their corresponding side lengths are congruent and the magnitude of their angles are congruent.
Now, we can write an equation that can be used to determine the tree's height. Since the ratio of the corresponding sides of similar triangles are equal in magnitude, we have the following mathematical expression (equation):
22.5/8.25 = x/5.5
Where:
x represents the height of the tree.
How tall is the tree?22.5/8.25 = x/5.5
Cross-multiplying, we have:
8.25x = 22.5 × 5.5
8.25x = 123.75
x = 123.75/8.25
x = 15 feet.
How far is the person standing from the tree?The distance of this person from the tree can be calculated as follows;
Distance = Length of tree's shadow - Length of person's shadow
Distance = 22.5 - 8.25
Distance = 14.25 feet.
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if the measure of an interior angle of a regular polygon is 120 degrees, how many sides does the polygon have?
Answer:
6 sides
Step-by-step explanation:
since the measure of an interior angle of a polygon can be found with the formula 180(n-2) / n where n is the number of sides we can substitute 120 to the answer and cross multiply to find that
120n = 180(n-2)
120n = 180n-360
360 = 60n
n = 6
In triangle , the measure of angle is 50° and the measure of angle 70°. What is the measure of the exterior angle to angle ?
Answer:
60
Step-by-step explanation:
50+70=120
180-20=60
Answer:
120°
Step-by-step explanation:
Your question didn't include an image or angle names, so it was pretty confusing to get what you were asking for. If you were asking for the exterior angle of the missing angle, then here's your answer:
The 3 angle measures of a triangle will always equal 180.
Since we've already got two angles, all we need to do is a simple equation to get our missing angle:
180-(50+70)=60
Now that we've got the missing angle, we need to calculate the exterior angle, the thing we're here for. We know (hopefully at this point) that an exterior angle and its interior angle are a linear pair, meaning that the two add up to 180. Knowing this, we can do this equation to finish off the question:
180-60=120
And there's your answer, 120°
There's also a shorter way of doing this, let me know if you'd like to see it. But for now, hope I helped!