Answer:
The sum of the expression (8 - 4i) + (-2 +7i) is (6 + 3i)
Step-by-step explanation:
In the complex numbers (a + bi) and (c + di), we can add the real parts together and the imaginary parts together, so their sum is
(a + bi) + (c + di) = (a + c) + (b + d)i
Let us use this fact to solve our question
∵ The complex numbers are (8 - 4i) and (-2 + 7i)
∴ Their sum = (8 - 4i) + (-2 + 7i)
∵ The real parts are 8 and -2
∵ 8 + -2 = 8 - 2 = 6
∴ The sum of the real parts is 6
∵ The imaginary parts are -4i and 7i
∵ -4i + 7i = 3i
∴ The sum of the the imaginary parts is 3i
∵ (8 - 4i) + (-2 + 7i) = (8 - 2) + (-4 + 7)i
∴ (8 - 4i) + (-2 + 7i) = 6 + 3i
∴ The sum of the expression (8 - 4i) + (-2 +7i) is (6 + 3i)
A student takes a multiple-choice test that has 10 questions. Each question has four choices. The student guesses randomly at each answer. Let X be the number of questions the student gets correct. (a) Find P(X = 3). (b) Find P(X > 2). (c) To pass the test, the student must answer 7 or more questions correctly. Would it be unusual for the student to pass? Explain.
Answer:
1)0.2502
2)0.475
3)0.003505
Step-by-step explanation:
Total No. of question n= 10
There are four choices in each question
So, Probability of success [tex]p = \frac{1}{4}[/tex]
Probability of failure q = [tex]1- \frac{1}{4}=\frac{3}{4}[/tex]
We will use binomial over here
[tex]P(X=x)=^nC_r p^r q^{n-r}[/tex]
1)
[tex]P(X = 3)=^{10}C_3 (\frac{1}{4})^3 (\frac{3}{4})^7\\P(X = 3)=\frac{10!}{3!7!} (\frac{1}{4})^3 (\frac{3}{4})^7\\P(X = 3)=0.2502[/tex]
2) [tex]P(X > 2)=1-P(X\leq 2)[/tex]
P(X>2)=1-(P(X=0)+P(X=1)+P(X=2))
[tex]P(X>2)=1-(^{10}C_0 (\frac{1}{4})^0 (\frac{3}{4})^{10}+(^{10}C_1 (\frac{1}{4})^1 (\frac{3}{4})^9+^{10}C_2 (\frac{1}{4})^2 (\frac{3}{4})^8)[/tex]
[tex]P(X>2)=1-((\frac{1}{4})^0 (\frac{3}{4})^{10}+(\frac{10!}{1!9!} (\frac{1}{4})^1 (\frac{3}{4})^9+\frac{10!}{2!8!} (\frac{1}{4})^2 (\frac{3}{4})^8)[/tex]
P(X>2)=0.475
3)
[tex]P(X\geq 7)=P(X=7)+P(X=8)+P(X=9)+P(X=10)\\\\P(X\geq 7)=^{10}C_7 (\frac{1}{4})^7 (\frac{3}{4})^{3}+(^{10}C_8 (\frac{1}{4})^8 (\frac{3}{4})^2+^{10}C_9 (\frac{1}{4})^9 (\frac{3}{4})^1+^{10}C_{10} (\frac{1}{4})^{10} (\frac{3}{4})^0\\\\P(X\geq 7)=\frac{10!}{7!3!} (\frac{1}{4})^7 (\frac{3}{4})^{3}+\frac{10!}{8!2!} (\frac{1}{4})^8 (\frac{3}{4})^2+\frac{10!}{9!1!} (\frac{1}{4})^9 (\frac{3}{4})^1+\frac{10!}{10!0!}(\frac{1}{4})^{10} (\frac{3}{4})^0\\\\P(X\geq 7)=0.003505[/tex]
a hill rises 10 meters over horizontal distance of 8 meters
calculate the slope
Answer:
Slope = 5/4
Step-by-step explanation:
GCF of 10 and 8 is 2, divide both values by two and have the 10 as the rise and 8 as the run.
Given the equation 5(-2x -10) = 25(x + 1), solve for the value of x that will make the equation true.
Answer:
Step-by-step explanation:
5(-2x -10) = 25(x + 1)
-10x - 50 = 25x + 25
by transposing
-10x - 25x = 25 + 50
-35x = 75
x = -75/35
x = 15/7
or 2.142857..... in decimal
Hope this helps
plz mark as brainliest!!!!!!!
What is the answer of 10% of 6340
Answer:
604
Step-by-step explanation:
just simple division pls giv 5 out ogf 5 and thanks
Answer:
634
Step-by-step explanation:
f(x) = x + 7, g(x) = x - 7
(a) (f + g)(x) =
(b) (f-g)(x)=
(c) (fg)(x)=
(d) (f/g)(x)=
a) 2x
b) 14
c) x^2 -49
d) -1
I'm doing sine, cosine, and tangent and I don't know what an opposite is in the triangle so if anyone can explain it in the most simple terms possible, that'd be great
Step-by-step explanation:
okay so basically when you have a triangle, the side that is directly across from the angle you are looking for is the "opposite". here is an attachment.
3g+5
(g-1)(g+6) for g = 3
answer as reduced fraction
please help omg im dying
Answer:
[tex] \frac{7}{9} [/tex]
Step-by-step explanation:
it seems like you're asking what the solution of each equation is put into a fraction
so, putting in 3 for g gives you
[tex]3(3) + 5 = 14[/tex]
which then goes over
[tex]((3) - 1 = 2)((3) + 6 = 9) = 18[/tex]
which gives
[tex] \frac{14}{18} [/tex]
however, this can be reduced to
[tex] \frac{7}{9} [/tex]
because both 14 and 18 can be divided by 2.
Evaluate 8 ÷ -2 · 4²+9. Thanks! Will give brainiest if possible
8) There are 6 cups of sugar in 5 batches of cookies. How many cups are in 1 poin
1 batch?
Answer:
6/5 cupsStep-by-step explanation:
[tex]6 \:cups = 5\:batches\\x\:cups = 1\:batch\\\\Cross\:Multiply\\\\5x = 6\\\\Divide\:both\:sides\:of\:the\:equation\:by\:5\\\\\frac{5x}{5} =\frac{6}{5} \\\\x = 1\frac{1}{5}[/tex]
Express 7.409 in word form.
32 students play basketball and 25 Students play
volleyball . It is found that 13 students play both
games. Find the number of students playing at least
one game
dotos numbers Sets
n
و
Answer:
44 students
Step-by-step explanation:
Given parameters:
Number of students playing basketball = 32
Number of students playing volleyball = 25
Number of students playing both = 13
Unknown:
Number of students playing at least one game = ?
Solution:
Let us first find the number of students that play basketball only and volleyball only.
Number of students playing basketball only = 32 - 13 = 19
Number of students playing volleyball only = 25 - 13 = 12
So,
Least number of students that play at least one game = number of students that plays basketball only + number of students that plays volleyball only + number of students that plays both;
= 19 + 12 + 13
= 44 students
There are two squares.
The larger square has an area of 1,089 square feet and the smaller square has an area of 121 square inches.
What is the scale factor between the two squares?
(A) 3
B
6
12
D 36
Answer:
It is 3
Step-by-step explanation:
Answer:
It is 3
Step-by-step explanation:
don’t look at graph... can someone answer
Answer:
Pretty much, it's just 46 times 7. So, you can do 322 jumping jacks in 7 minutes.
Please mark me as Brainliest, I need it to move onto the next level. =D
Analysing the Question:
We are given the function:
f(x) = 46x
where x is the number of minutes and f(x) is the number of jumping jacks in the given number of minutes
Number of jumping jacks in 7 minutes:
replacing x with number of minutes (i.e, 7). We get:
f(7) = 46*7
f(7) = 322 jumping jacks
Divide: 3/8 ÷ 5/12 = ?
flip 5/12 to be 12/5 to make this equation multiplication
3/8*12/5 = 36/40 = 18/20 = 9/10
The solution of expression is,
⇒ 9 / 10
We have to given that;
To Divide,
⇒ 3/8 ÷ 5/12
Now, We can divide the numbers as;
⇒ 3/8 ÷ 5/12
⇒ 3/8 × 12/5
⇒ 36 / 40
⇒ 18/20
⇒ 9 / 10
Thus, The solution of expression is,
⇒ 9 / 10
Learn more about the divide visit:
https://brainly.com/question/28119824
#SPJ6
The toco toucan, the largest member of the toucan family, possesses the largest beak relative to body size of all birds. This exaggerated feature has received various interpretations, such as being a refined adaptation for feeding. However, the large surface area may also be an important mechanism for radiating heat (and hence cooling the bird) as outdoor temperature increases. Here are data for beak heat loss, as a percent of total body heat loss, at various temperatures in degrees Celsius:
Temperature (degrees Celsius) 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
Percent heat loss from beak 35 36 38 28 41 43 55 46 39 54 45 58 60 56 62 67
a. The equation of the least-squares regression line for predicting beak heat loss, as a percent of total body heat loss from all sources, from temperature is: _____ (Use decimal notation. Give your answer to four decimal places.)
b. Use the equation to predict (
±
0.01) beak heat loss, as a percent of total body heat loss from all sources, at a temperature of 25 degrees Celsius.
c. What percent (
±
0.01) of the variation in beak heat loss is explained by the straight-line relationship with temperature?
d. Find the correlation r (
±
0.001) between beak heat loss and temperature.
Answer:
Kindly check explanation
Step-by-step explanation:
Given the data:
Temperature (degrees Celsius) : 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
Percent heat loss from beak : 35 36 38 28 41 43 55 46 39 54 45 58 60 56 62 67
Using an online regression calculator ; the regression equation obtained is :
ŷ = 2.0927X + 0.6029
X = independent variable
Y = predicted variable
2.0927 = slope
0.6029 = intercept
B.) temperature = 25
ŷ = 2.0927(25) + 0.6029
= 52.9204
C.) the explained variance is the value of the coefficient of determination (R²) which is the square of the correlation Coefficient
0.8785² = 0.7718
D.) the correlation Coefficient r is 0.8785 using the Coefficient of regression calculator
9. Determine whether KM and ST are parallel, perpendicular, or neither. K(-1, -8), M(1,6), S(-2,-6), T(2, 10) A Parallel B Perpendicular C Neither Hint(use slope formula)
Plz do fast I need it for a test The front view of a tent is.shown below if a zipper.is going to be put in along the length x how long should the.zipper be
Answer:
x=15ft
Step-by-step explanation:
a^2+b^2=c^2
8^2+b^2=17^2
b^2+64=289
b^2=225
b=15
justin walk 5 kilometer and he turn right and he swim 35 meters why the apple is red?
Answer:
Red apples get their color from anthocyanins. These are pigments, or natural colorings, that develop as the apple grows. It absorbs all the colors of the rainbow—except for red. The red light reflects off the apple and our brain and eyes work together to let us know what color we are seeing
Step-by-step explanation:
The first part of the question does not correlate to the final question the problem is asking. Therefore, we just need to find out why apples are red. A simple google search can tell you why ^^
Answer:
it's nature first it's green after its gets ready to eat it's colour change
in am just joking
Define cross-multiplication property
Answer: Not to be confused with Cross product.
In mathematics, specifically in elementary arithmetic and elementary algebra, given an equation between two fractions or rational expressions, one can cross-multiply to simplify the equation or determine the value of a variable.
The method is also occasionally known as the "cross your heart" method because a heart can be drawn to remember which things to multiply together and the lines resemble a heart outline.
A population has standard deviation g = 17.2.
Part 1 of 2
(a) How large a sample must be drawn so that a 99.8% confidence interval for I will have a margin of error equal to 3.8?
Round the critical value to no less than three decimal places.
Round the sample size up to the nearest integer.
A sample size of is needed to be drawn in order to obtain a 99.8% confidence interval with a margin of error equal to
3.8.
Part 2 of 2
(b) If the required confidence level were 80%, would the necessary sample size be larger or smaller?
(Choose one) because the confidence level is (Choose one)
х
Answer:
idk
Step-by-step explanation:
A doctor gives a patient a 70% chance of surviving bypass surgery after a heart attack. If the patient
Isurvives the surgery, then the patient has a 40% chance that the heart damage will heal. Find the
probability that the patient survives the surgery and the heart damage heals. The probability is nothing
Answer:
The probability the person will survive the bypass surgery and that the heart damage will heal is about 28%
Step-by-step explanation:
(7/10)*(4/10)*100=28
To solve for probability of situations like this you have to multiply the fractional values of the two percentages and multiply by 100 to get the new percentage.
Using conditional probability, it is found that there is a 0.28 = 28% probability that the patient survives the surgery and the heart damage heals.
Conditional Probability:
[tex]P(B|A) = \frac{P(A \cap B)}{P(A)}[/tex]
In which
P(B|A) is the probability of event B happening, given that A happened. [tex]P(A \cap B)[/tex] is the probability of both A and B happening. P(A) is the probability of A happening.In this problem:
Event A: Surviving.Event B: Healing.70% chance of surviving, thus [tex]P(A) = 0.7[/tex].If the patient survives, 40% chance of healing, thus [tex]P(B|A) = 0.4[/tex].The probability of both is [tex]P(A \cap B)[/tex], then:
[tex]P(B|A) = \frac{P(A \cap B)}{P(A)}[/tex]
[tex]P(A \cap B) = P(B|A)P(A)[/tex]
[tex]P(A \cap B) = 0.4(0.7)[/tex]
[tex]P(A \cap B) = 0.28[/tex]
0.28 = 28% probability that the patient survives the surgery and the heart damage heals.
A similar problem is given at https://brainly.com/question/24161830
Sixteen years after purchasing shares in a mutual fund for $6200, the shares are sold for $11,000. The the total return is %.
9514 1404 393
Answer:
77.42%
Step-by-step explanation:
The increase in value is ...
(11000/6200 -1) × 100% ≈ 77.42%
The center of an ice rink is located at (0, 0) on a coordinate system measured in meters. Susan is skating along a path that can be modeled by the equation y = 6x – x2 – 5. Luke starts at (10, –21) and skates along a path that can be modeled by a quadratic function with a vertex at (8, –9). If the rink is a circle with a radius of 35 meters, which statement best interprets the solution(s) of a system of equations modeling the paths of the skaters?
A. The skaters’ paths intersect once, but that point is outside the rink.
B. The skaters’ paths intersect once, and that point is inside the rink.
C. The skaters’ paths intersect twice, but only one of those points is inside the rink.
D. The skaters’ paths intersect twice, and both points are inside the rink.
Answer:
Option C:The skaters path intersect twice, but only one of those points is inside the rink.
Step-by-step explanation:
Coordinates of center of ice rink: (0,0) Radius of ice rink circle = 35 m
We know that the equation of a circle with center coordinates (a,b) and radius of (r) is given as; (x - a)² + (y - b)² = r²
Thus, the total area on which the skaters are skating will be given by the equation;
x² + y² = 35²
Now, we are told the path along which Susan is skating is modeled by the equation: y = 6x - x² - 5
While Luke starts at (10, –21) and skates along a path that can be modeled by a quadratic function with a vertex at (8, –9)
From equation of a parabola, the path along which like is skating can be modeled by;
(x - 8)² = 4a(y + 9)
To find a, we will substitute the coordinate started at to get;
(10 - 8)² = 4a(-21 + 9)
4 = 4a × -12
Divide both sides by 4 to get;
a = -1/12
Thus;
(x - 8)² = 4(-1/12)(y + 9)
(x - 8)² = (-1/3)(y + 9)
This gives: 3(x - 8)² = -(y + 9)
I've drawn the graph on demos and attached it.
From the graph we can see that the skaters points intersect twice but one is inside the rink circle while the other is outside the rink circle. The point at which they intersect outside the rink was slightly cropped out because of size. But it is clearly seen that they are both approaching point of intersection.
Thus, correct answer is Option C.
Answer:
C
Step-by-step explanation:
just took the quiz
A club had some money to purchase new chairs. After buying 355 chairs at $199 each, there was $1,068 remaining. How much money did the club have at first? *
Answer:
$71713
Step-by-step explanation:
If each chair cost $199 then multiple 199 by 355
[tex]199*355= 70645[/tex]
If they still have 1068 then add that into the sum
[tex]70645+1068=71713[/tex]
So your answer is $71713
Answer: $71,713
Step-by-step explanation:
First you would multiply 355 by 199 to get 70,645. Next you would add the remainder of what they had, $1,068, and get the answer. hope this helps.
Find both the greatest common factor and the least common multiple of 24 and 30.
Answer:
24 = 2, 3 , 4, 6, 8, 12, 24
30 = 2, 3, 5, 6, 10, 15, 30
Step-by-step explanation:
Least common for both is 2
Greatest common factor for both is 6
Tara's website, verdantveggies.com, specializes in the sale of rare or unusual vegetable seeds. Tara sells packets of sweet-pepper seeds for $2.85 each and packets of hot-pepper seeds for $4.29 each. She also offers a 16-packet mixed-pepper assortment combining packets of both types of seeds at $3.30 per packet. How many packets of each type of seed are in the assortment?
Answer:
Let's define the variables:
S = # of sweet pepper seeds in the mix pack.
H = # of hot pepper seeds in the mix pack.
Let's suppose that $3.30 is the mean price of the seeds in the mix pack.
Then we have two equations:
S + H = 16.
(S*$2.85 + H*$4.29)/16 = $3.30
Now let's solve this system.
The first step is isolating one variable in one of the equations, i will isolate S in the first equation.
S = 16 - H.
Now we can replace this in the second equation, and solve it for H.
( (16 - H)*$2.85 + H*$4.29)/16 = $3.30
( (16 - H)*$2.85 + H*$4.29) = $3.30*16 = $52.80
$45.60 + H*$1.44 = $52.80
H*$1.44 = $52.80 - $45.60 = $7.20
H = $7.20/$1.44 = 5
Then in the mix pack there are 5 hot-pepper seeds.
And the other 11 must be sweet-pepper seeds
Algebraic equations are equations that contain unknown variables.
The number of packets of sweet-pepper seeds is 11 and the number of packets of hot-pepper seeds is 5.
Let's represent:is
The number of packets of sweet-pepper seeds = s
The number of packets of hot-pepper seeds = h
Based on this question, our system of equations are:
$2.85 x s + $4.29 x h = $3.30(16)
2.85s + 4.29h = 52.8...........Equation 1
s + h = 16...........Equation 2
s = 16 - h
We substitute 16 - h for s in Equation 1
2.85(16 - h) + 4.29h = 52.8
45.6 -2.85h + 4.29h = 52.8
Subtract 45.6 from both sides
45.6 - 45.6 -2.85h + 4.29h = 52.8 - 45.6
1.44h = 7.2
h = 5
There are 5 hot-pepper seeds in the assortment.
Solving for the number of sweet-pepper seeds.
s = 16 - h
s = 16 - 5
s = 11
There are 11 sweet-pepper seeds in the assortment.
Therefore, the number of packets of sweet-pepper seeds is 11 and the number of packets of hot-pepper seeds is 5.
To learn more, visit the link below:
brainly.com/question/12978834
Are these questions different at all? And if so whats the answer to them?
Answer:
i think u got it
Step-by-step explanation:
If a person walks 1/3 of a mile every 1/6 of an hour, what is their speed in miles per hour?
Answer:
2 mi per hour
Step-by-step explanation:
1/3*6=
6/3= 2
2 mi per hour
Answer:
2mph
Step-by-step explanation:
If a person walks 1/3 of a mile every 1/6 of an hour you divide to solve.
[tex]\frac{\frac{1}{3}}{\frac{1}{6}}[/tex] To solve you flip the bottom and multiply:
[tex]\frac{1}{3} *\frac{6}{1}[/tex] = [tex]\frac{6}{3} = 2[/tex]
The person is walking 2mph
−20=−4x−6x Find the value of x
Answer:
[tex]\huge\boxed{x=2}[/tex]
Step-by-step explanation:
[tex]-20=-4x-6x\qquad|\text{combine like terms}\\\\-20=-10x\qquad|\text{divide both sides by (-10)}\\\\\dfrac{-20}{-10}=\dfrac{-10x}{-10}\\\\2=x\to x=2[/tex]
if m 2 =6x+8 and m 6 = 8x-6, find the value of x so that l is parallel to m
Answer:
[tex]x = 7[/tex]
Step-by-step explanation:
Given
[tex]m_2 = 6x + 8[/tex]
[tex]m_6 = 8x - 6[/tex]
Required
Determine x when both lines are parallel
For parallel lines, slopes must be equal.
i.e.
[tex]m_1 = m_2[/tex]
In this case,
[tex]m_6 = m_2[/tex]
Substitute values for m6 and m2
[tex]8x - 6 = 6x + 8[/tex]
Collect Like Terms
[tex]8x - 6x = 8 + 6[/tex]
[tex]2x = 14[/tex]
Solve for x
[tex]x = 14/2[/tex]
[tex]x = 7[/tex]
Answer:7
Step-by-step explanation: