Answer: -3y + 8z
Step-by-step explanation:
2x -2x = 0
-2y + - y= -3y
5z + 3z= 8z
-3y + 8z
The expression 2x − 2y + 5z − 2x − y + 3z is simplified as − 3y + 8z.
What is simplification?Making anything easier to accomplish or comprehend, as well as making it less difficult, is the definition of simplification.
PEMDAS rule means for the Parenthesis, Exponent, Multiplication, Division, Addition, and Subtraction. This rule is used to solve the equation in a proper and correct manner.
The expression is given below.
⇒ 2x − 2y + 5z − 2x − y + 3z
Simplify the expression, then we have
⇒ 2x − 2y + 5z − 2x − y + 3z
⇒ 2x − 2x − 2y − y + 5z + 3z
⇒ 0 − 3y + 8z
⇒ − 3y + 8z
The expression 2x − 2y + 5z − 2x − y + 3z is simplified as − 3y + 8z.
More about the simplification link is given below.
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The Guzman family lives 240 miles from Mexico City. If the Guzmans travel in
their car at 60 miles per hour, how long does it take for them to get to Mexico
Answer:
4 hours
Step-by-step explanation:
To find the time it takes to travel the distance, divide the distance by the speed they are going.
(240 miles)/(60 miles per hour) = 4 hours
It will take them 4 hours.
Answer:Answer:
4 hours
Step-by-step explanation:
To find the time it takes to travel the distance, divide the distance by the speed they are going.
(240 miles)/(60 miles per hour) = 4 hours
It will take them 4 hours.
Step-by-step explanation:
Solve for x 4x+8=6x−1 Give your answer as an improper fraction in its simplest form.
Answer:
Step-by-step explanation:
4x+8=6x-1
-4x . =-4x .
8 = 2x-1
-1+8=2x-1+1
7=2x
7/2= 2x/2
3.5=x
The value of x will be;
⇒ x = 9/2
What is an expression?
Mathematical expression is defined as the collection of the numbers variables and functions by using operations like addition, subtraction, multiplication, and division.
Given that;
The expression is,
⇒ 4x + 8 = 6x - 1
Now,
Solve the expression for x as;
⇒ 4x + 8 = 6x - 1
Subtract 6x both side, we get;
⇒ 4x + 8 - 6x = 6x - 1 - 6x
⇒ - 2x + 8 = - 1
Subtract 8 both side,
⇒ - 2x = - 1 - 8
⇒ - 2x = - 9
Divide by - 2 as;
⇒ x = 9/2
Thus, The value of x will be;
⇒ x = 9/2
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The width of a rectanglular solid is twice the height of the solid, the height of the solid is twice the length of the solid. If x is the length of the solid, what is the surface area in terms of x?
Answer:
28x^2
Step-by-step explanation:
Set variables:
Width = w
Length = x
Height = h
Set Equation:
w = 2h = 4x
h = 2x
x=x
Now that we have the terms in terms of x, we can find surface area.
We find the first three then multiply answer by 2, because there are 6 sides.
w*h -> first side
w*x -> second side
h*x -> third side
Set them in terms of x:
4x*2x = 8x^2
4x*x = 4x^2
2x*x = 2x^2
Add them and get: 14x^2
Wait, you need to multiply them by 2 and get: 28x^2
Answer: The answer is in the photo I really hope it’s right
Step-by-step explanation: I don’t need a brainly(I’m joking)
Hahahaha I know it’s not the best
The population of the world was 7.1 billion in 2013, and the observed relative growth rate was 1.1% per year. (a) Estimate how long it takes the population to double. (Round your answer to two decimal places.)
Answer:
90.91 years
Step-by-step explanation:
If the rate of population of the world was 7.1 billion in 2013, and the observed relative growth rate was 1.1% per year, increase in yearly population = 1.1/100 × 7,100,000,000
= 1.1 × 71,000,000
= 78,100,000
The amount increases by 78.1million every year.
To know how long it will take the population to double.
double of the initial population = 2×7,100,000,000 = 14,200,000,000
Increment per year = 78,100,000
Time it will take for the population to double = 7,100,000,000/78,100,000
= 90.91
≈ 91
This means it will take about 90.91years for the population to double
You Identify the ratio of the average number of bass to the averg
Answer:
Step-by-step explanation:
Using six random samples, the average number of catfish in the samples was 5.7
Answer:
Uhhhh......Hi??
y
10
1
B(7,9)
Create a rectangle around the parallelogram. The
dimensions of this rectangle are
Find the area of the four right triangles surrounding the
parallelogram. The total area of the triangles is
square units
Subtract the triangle areas from the area of the
rectangle to obtain the area of the parallelogram. The
area of parallelogram ABCD is square units.
6
2
-10
6
-6
A-3,-1)
-2
10
C(8, -1)
D(-2,-11)
Answer:
rectangle: 11 × 20triangle area: 110 u²parallelogram area: 110 u²Step-by-step explanation:
See below for a graph showing the parallelogram and the rectangle.
The dimensions of the rectangle are 11 by 20. The rectangle area is ...
rectangle area = bh = (11)(20) = 220 . . . square units
There are 2 right triangles with a base of 10 and a height of 1. There are 2 right triangles with a base of 10 and a height of 10. The total area of the triangles is ...
triangle area = 2(1/2)(10)(1) +2(1/2)(10)(10) = 10(1 +10) = 110 . . . square units
The area of the parallelogram is the difference of these, ...
parallelogram area = rectangle area - triangle area
= (220 units²) -(110 units²) = 110 units²
The area of parallelogram ABCD is 110 square units.
_____
Check
The parallelogram has a base of 10√2 and a height of 5.5√2, so an area of (10√2)(5.5√2) = 110 square units. This matches the above result.
Answer:
1) 11 by 20 2) 110 3) 110 correct on edg
Step-by-step explanation:
Create a rectangle around the parallelogram. The dimensions of this rectangle are
11 by 20
Find the area of the four right triangles surrounding the parallelogram. The total area of the triangles is
110 square units.
Subtract the triangle areas from the area of the rectangle to obtain the area of the parallelogram. The area of parallelogram ABCD is
110 square units.
7. The value of a computer has a decay factor of 0.85 per year. After 2 years, the computer is worth $1445. What was the original value of the computer?
Answer:
$64222.22
Step-by-step explanation:
If we call the original value as x, we can write:
1445 = x * (0.15)² (Note: We write 1 - 0.85 = 0.15 and not 0.85 because 0.85 is the decay factor)
1445 = 0.0225x
x ≈ 64222.22
Answer:
$ 2000Step-by-step explanation:
Let the original value be $ X
Decay factor = 0.85
Time = 2 years
Reduced value = $ 1445
Now,
Reduced value = original value * (decay)[tex] {}^{number \: of \: years} [/tex]
Plug the values
[tex]1445 = x \times {(0.85)}^{2} [/tex]
Evaluate the power
[tex]1445 = x \times 0.7225[/tex]
[tex]x = \frac{1445}{0.7225} [/tex]
Calculate
[tex]x = 2000[/tex]
Hope this helps...
Best regards!!
Determine the number of terms in the sequence: 5240,4365, 3490, 2615, ..., -2635
Answer:
I believe the number of terms are 10
Step-by-step explanation:
The number of terms in the given sequence(5240,4365, 3490, 2615, ..., -2635) is 10.
What is a sequence?In mathematics, a sequence is an enumerated group of elements in which repetitions are allowed and order is significant.
How to solve this problem?The 1st term in the given sequence is 5240
The 2nd term is 4365 = 5240 - 875
The 3rd term is 3490 = 4365 - 875
The 4th term is 2615 = 3490 - 875
Then the 5th term is 2615 - 875 = 1740
The 6th term is 1740 - 875 = 865
The 7th term is 865 - 875 = - 10
The 8th term is - 10 - 875 = - 885
The 9th term is - 885 - 875 = - 1760
The 10 the term is - 1760 - 875 = - 2635.
Therefore the number of terms in the given sequence(5240,4365, 3490, 2615, ..., -2635) is 10.
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9. (09.01 LC) The graphs of f(x) and g(x) are shown below: If f(x) = (x + 7)^2, which of the following is g(x) based on the translation? (5 points)
g(x) = (x + 9)^2
g(x) = (x + 5)^2
g(x) = (x − 9)^2
g(x) = (x − 5)^2
Hey there! :)
Answer:
g(x) = (x + 9)²
Step-by-step explanation:
If we look at the graph g(x), we can see that its vertex is at (-9, 0).
Recall the transformation form of a parabola is f(x) = ±a(b(x-h))+k where (h , k) are the coordinates of the vertex. In this instance it is (-9, 0), therefore:
g(x) = (x + 9)²
Factor 28+56t+28w28+56t+28w28, plus, 56, t, plus, 28, w to identify the equivalent expressions. Choose 2 answers:
Answer: The factorization of [tex]28+56t+28w[/tex] [tex]=28(1+2t+w)[/tex]
The factors of [tex]28+56t+28w[/tex] are 28 and 1+2t+w.
Step-by-step explanation:
The given expression : [tex]28+56t+28w[/tex]
To factorize it, we need to find the common factor.
As 56 can be written as 2 x 28.
So, the above expression would become
[tex]28+2\times28t+28w[/tex]
Now, taking 28 as common from all the terms, we will get
[tex]28(1+2t+w)[/tex]
Thus, the factorization of [tex]28+56t+28w[/tex] [tex]=28(1+2t+w)[/tex]
And the factors of [tex]28+56t+28w[/tex] are 28 and 1+2t+w.
Answer:
b&d
Step-by-step explanation:
i did khan on it and got it right
What is the sign of 123 1/23 + (-123 1/23) A) positive B) negative C) zero
Answer:
Positive
Step-by-step explanation:
123 1/23 + (-123 1/23)
Opening the bracket, we have ;
123 1/23 - 123 1/23 = 0
Kindly note that 0 is not a sign, so we cannot select it as an option.
0 is a positive number and not negative.
Thus the sign we have is the positive sign and that gives our answer
Multiply. 2 3/4* 4/5 Choose 1 answer: (a) 2 7/20 (b) 2 1/5 (c) 1 3/5 (d) 11/20
Answer:
[tex]\boxed{\red{ \frac{11}{5} = 2 \frac{1}{5} }}[/tex]
Answer B is correct.
Step-by-step explanation:
[tex]2 \frac{3}{4} \times \frac{4}{5} \\ \frac{11}{4} \times \frac{4}{5} \\ \frac{44}{20} \\ = \frac{11}{5} = 2 \frac{1}{5} [/tex]
Answer:
Hello!
_____________________
Exact Form: [tex]\frac{11}{5}[/tex]
Decimal Form: 2.2
Mixed Number Form: [tex]2\frac{1}{5}[/tex]
Step-by-step explanation: Simplify the expression.
So your anwser woould be ( B ) 2 1/5
Hope this helped you!
:D
I’m really not sure what the answer to this question is, can anyone help?
Answer:
25(sqrt(2)+1)
Some explanation:
The exact form is 25*sqrt(2) + 25.
If we divide by 25, we are left with sqrt(2) + 1.
So 25(sqrt(2) + 1) is the correct answer.
Hope that helps a little!
Which type of conic section is described by the following equation? Please helpppp plzzzz
Answer: Choice F. Hyperbola opening up and down.
======================================================
Explanation:
The subtraction symbol between the two fractions indicates right off the bat that we're dealing with a hyperbola. The question now is "How does it open? Does it open up/down? Or does it open left/right?"
To answer this new question, we just need to look at which fraction is negative. The fraction with x in it is negative, so that means the y fraction is positive. The y fraction being positive is the indication of the hyperbola opening up/down.
Find the domain from the ordered pair {(1, 1), (2, 4), (3, 9), (4, 16)}
Answer:
{ 1 , 2 , 3 , 4 }Explanation:
Domain and Range:Let R be a relation from A to B. Then the set of first components or the set of elements of A are called domain and the set of second components or the set of elements of B are called the range.
Hope this helps...
Good luck on your assignment..
graph the linear inequality shown below on the provided graph
Answer:
I added the graph to this answer (png form)
Step-by-step explanation:
The graph is attached below:
What is graph?Graph is a mathematical representation of a network and it describes the relationship between lines and points.
given:
[tex]y\le\ \frac{1}{3}\ x\ -6\[/tex]
The inequality shown above is defined by the graph attached below.
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Claim: Most adults would not erase all of their personal information online if they could. A software firm survey of 604 randomly selected adults showed that 49.5% of them would erase all of their personal information online if they could. Make a subjective estimate to decide whether the results are significantly low or significantly high, then state a conclusion about the original claim.
The results (ARE; ARE NOT) significantly (LOW; HIGH) so there (IS; IS NOT) sufficient evidence to support the claim that most adults would erase all their personal information online if they could.
Answer: The results ARE NOT significantly HIGH so there IS NOT sufficient evidence to support the claim that most adults would erase all their personal information online if they could.
Step-by-step explanation:
To find 49.5% of 604-
49.5 ÷ 100 = 0.495
0.495 x 604 = 298.98 = 299 (I have rounded to make the estimate easier)
When someone say MOST, it usually means more than half of the total. If I divide 604 by 2 (basically halving it) it gives me 302.
299 is close enough to 302, but even if got 302 as my first result instead of 299, it is still too less to be called MOST. Therefore,
The results ARE NOT significantly HIGH so there IS NOT sufficient evidence to support the claim that most adults would erase all their personal information online if they could.
Hope this helps :)
PLEASE HELP ASAP!!:
explain the answer to this as well, please :)
the difference between two numbers is 4. the sum of the smaller number and theee times the larger number is 36. what are the two numbers?
I totally typed the right answer for the wrong question sorry
Tim is investigating the relationship between the number of years since a tree was planted and the height of the tree in feet. His data are shown in the table.
Years Since Tree was Planted vs. Height of Tree
Years since tree was planted, x
Height of tree in feet, y
2
17
3
25
5
42
6
47
7
54
9
69
Using a regression calculator, what is a good prediction for the height of the tree when it is 100 years old?
A calculator screen. A 2-column table with 6 rows titled Data. Column 1 is labeled x with entries 2, 3, 5, 6, 7, 9. Column 2 is labeled y with entries 17, 25, 42, 47, 54, 69. The regression equation is y almost-equals 7.36 x + 3.08; r almost-equals 0.998.
A good prediction for the height of the tree when it is 100 years old is about 315 feet because that is what the trend line, y almost-equals 3.08 x + 7.36, produced by the regression calculator predicts.
A good prediction for the height of the tree when it is 100 years old is about 739 feet because that is what the trend line, y almost-equals 7.36 x + 3.08, produced by the regression calculator predicts.
There is not a good prediction for the height of the tree when it is 100 years old because the trend line produced by the regression calculator does not give a prediction.
There is not a good prediction for the height of the tree when it is 100 years old because the prediction given by the trend line produced by the regression calculator probably is not valid that far in the future.
Answer: There is not a good prediction for the height of the tree when it is 100 years old because the prediction given by the trend line produced by the regression calculator probably is not valid that far in the future.
Step-by-step explanation:
Years since tree was planted (x) - - - - height (y)
2 - - - - 17
3 - - - - 25
5 - - - 42
6 - - - - 47
7 - - - 54
9 - - - 69
Using a regression calculator :
The height of tree can be modeled by the equation : ŷ = 7.36X + 3.08
With y being the predicted variable; 7.36 being the slope and 3.08 as the intercept.
X is the independent variable which is used in calculating the value of y.
Predicted height when years since tree was planted(x) = 100
ŷ = 7.36X + 3.08
ŷ = 7.36(100) + 3.08
y = 736 + 3.08
y = 739.08
Forward prediction of 100 years produced by the trendline would probably give an invalid value because the trendline only models a range of 9 years prediction. However, a linear regression equation isn't the best for making prediction that far in into the future.
Answer:
D
Step-by-step explanation:
There is not a good prediction for the height of the tree when it is 100 years old because the prediction given by the trend line produced by the regression calculator probably is not valid that far in the future.
Gold-192 is a radioactive isotope with a half-life of 4.95 hours. How long would it take for a 25 gram sample of Gold-192 to decay until only 2 grams remain? a. about 9.1 hours b. about 31 hours c. about 18 hours d. about 61.9 hours
Answer:
Step-by-step explanation:
The formula you will need for this is:
[tex]A=A_0(\frac{1}{2})^{\frac{t}{H}[/tex] where A is the amount after some decay has happened, A₀ is the intial amount, t is the time in hours, and H is the half-life in hours. Those values for us are:
A = 2 g
A₀ = 25 g
H = 4.95 hrs and
t = ?
Filling in:
[tex]2=25(\frac{1}{2})^{\frac{t}{4.95}[/tex] Keep in mind that, because of the nature of the exponential form of this equation, you CANNOT simply multiply the 25 by the 1/2. Exponential equations don't work that way. Begin instead by dividing both sides by 25 to get
[tex].08=(\frac{1}{2})^{\frac{t}{4.95}[/tex] The goal is to get that t out from its exponential position. Do that by taking the natural log of both sides:
[tex]ln(.08)=ln(.5)^{\frac{t}{4.95}[/tex]
After you take the natural log of the right side, the property allows you to bring the exponent down out front:
[tex]ln(.08)=\frac{t}{4.95}ln(.5)[/tex]
Now divide both sides by ln(.5) to get
[tex]\frac{ln(.08)}{ln(.5)}=\frac{t}{4.95}[/tex]
Simplify the left side out on your calculator to get
[tex]\frac{-2.525728644}{-.6931471806}=\frac{t}{4.95}[/tex] and then divide:
[tex]3.643856=\frac{t}{4.95}[/tex]
Finally, multiply both sides by 4.95 to get
3.643856(4.95) = t so
t = 18.0 hours which is choice C
Please answer it in two minutes
Answer:
8√3
Step-by-step explanation:
Sin 30 =4√3/DE
DE = 4√3/Sin30 = 8√3
Which of the following is a set in correct set notation?(1,2,3){4,5,6} the letters of the alphabet 7,8,9
Answer: {4,5,6}
Step-by-step explanation: Sets could be explained as a representation of elements which could be numbers, alphabets or a collection of items which are wrapped inside a curly bracket {}. Generally in mathematical or statistical parlance, once elements are wrapped around curly braces, the collection of those emmts is called a set. And therefore, set arithmetic such as union, intersection, complement e.t.c can be performed on elements of the given set. Elements wrapped in curly braces signifies that the elements reperesents an entire entity.
In the question given above, {7,8,9} reperesents a set containing three elements : 7, 8,9.
Hello i need some help
Answer:
y = 2x - 1
Step-by-step explanation:
(3, 5) (5, 9)
slope = (9-5)/(5-3) = 4/2 = 2
y = mx + b
5 = 2(3) + b
-1 = b
y = 2x -1
Answer:
f(x)=2x-1; y=2x-1
Step-by-step explanation:
First we need to find the slope and to do so you use the equation [tex]\frac{y_{1} -y_{2}}{x_{1}-x_{2}}[/tex] .
Plugging in for the values we get (9-5)/(5-3)=4/2=2, which means we have a slope of 2.
Now we just have to find the y-intercept, and to do this we multiply the x-value by the slope (2) and see what we have to add to that to get the y-value.
For example, 5*2=10, 10-1=9, so -1 is our y-intercept.
This means our equation in slope-intercept form is y=2x-1 and in function form is f(x)=2x-1
5x + y = 2
2x-3y = 62
Hey there! :)
Answer:
x = 4, y = -18 or (4, -18).
Step-by-step explanation:
Given:
5x + y = 2
2x - 3y = 62
We can use substitution to solve this problem. Rearrange the first equation in terms of y:
5x + y = 2 ---> y = -5x + 2
Substitute in this equation for y into the second equation:
2x - 3(-5x + 2) = 62
Distribute -3:
2x + 15x - 6 = 62
Combine like terms:
17x - 6 = 62
Add 6 to both sides:
17x = 68
Divide both sides by 17:
x = 4.
Plug in this value for x into an equation to solve for y:
5(4) + y = 2
20 + y = 2
y = -18.
Therefore, the solutions to this system of equations are:
x = 4, y = -18 or (4, -18).
help i need help quick I will mark u brainllest
Answer:
C
∠L and∠Q
Step-by-step explanation:
in the congruence statementit shows
A. JL and PR
JKL≅PQR
THEY MATCH-not this one
B. ∠K and ∠Q
JKL≅ PQR
THEY MATCH-not this one
C.∠L and ∠Q
JKL≅PQR
THEY DO NOT MATCH
D. ∠J and ∠P
JKL≅PQR
THEY MATCH-not this one
An archeologist in Turkey discovers a spear head that contains 27% of its original amount of C-14
Answer:
it is 13093 i got it correct
(05.03 MC)
An observer (O) spots a plane (P) taking off from a local airport and flying at a 23° angle horizontal to her line of sight and located directly above a tower (T). The observer also notices a bird (B) circling directly above her. If the distance from the plane (P) to the tower (T) is 5,000 feet, how far is the bird (B) from the plane (P)? Round to the nearest whole number.
Step-by-step explanation:
let x be the distance between B and P
tan(67)=x/5000
x=2.3558 . 5000
x=11779feet
Answer:
11,779 feet
Step-by-step explanation:
Is the answer
What is the additive inverse of x if x equals -32
Answer:
32
Step-by-step explanation:
The additive inverse means, the opposite sign,
for example the additive inverse means -2 turns into 2.
So -32 would be 32.
Answer:
[tex]\boxed{x=32}[/tex]
Step-by-step explanation:
The additive inverse of a number is the opposite of that number.
-32 opposite is 32.
PLEASE HELP ME PLEASE I NEED TO PASS. WILL MARK BRAINLIEST!!!! WILL REPORT IF COMMENTED AS AN ANSWER TO GET POINTS. I FR NEED HELP
Answer:
1. 29.44 feet.
2. 2/3.
3. 10/9.
4. 39/5.
Step-by-step explanation:
1. 34-foot ladder makes a 60 degree angle with the ground. If you visualize a 30-60-90 triangle with the ladder and the building and the ground, you can see that the hypotenuse of the triangle is 34 feet.
With 30-60-90 triangles, the short side is x, the hypotenuse is 2x, and the long side is x and the square root of 3.
If the hypotenuse is 34 feet, that must mean that the short side is 34 / 2 = 17 feet. The long side will be 17 * sqrt(3) = 17 * 1.732050808 = 29.44486373. So, the height above the ground will be about 29.44 feet.
2. Tangent of A! For this, we will use SOH CAH TOA... TOA stands for tangent: opposite over adjacent.
According to the diagram, angle A has an adjacent side of 15 units and an opposite side of 10 units. That means that tanA = 10 / 15 = 2/3.
If you want to find the measure of angle A, you can easily find the cotangent of 2/3. That is 33.69006753, or about 34 degrees.
3. The ratio should be 5 feet to 54 inches. There are 12 inches in 1 foot, so 5 feet is the same thing as 60 inches. 60 / 54 = 30 / 27 = 10/9.
4. (p + 9) / 7 = 12 / 5
5(p + 9) = 12 * 7
5p + 45 = 84
5p = 39
p = 7.8
That is the same thing as 7 and 4/5, or (35 + 4)/5 = 39/5
Really hope this helps!!
Answer to #4:a=−p2+84/p (note:the p2 is p to the exponent of 2, not p times 2)
Explanation:
Step 1:Multiply both sides by p
1/7ap+1/7p2=12
Step 2:Step 2: Add (-1)/7p^2 to both sides.
1/7ap+1/7p2+(−1/7p2)=12+(−1/7p2)1/7ap=−1/7p2+12
1/7ap=−1/7p2+12
Step 3: Divide both sides by p/7. and you get..
a=−p2+84/p
note:the p2 is p to the exponent of 2, not p times 2
if -1 and-2 are the zeroes of the cubic polynomial x³-2x²+ax+b, then find the value of a and b
Answer:
a = - 13, b = - 10
Step-by-step explanation:
Given that x = - 1 and x = - 2 are zeros then
f(- 1) = 0 and f(- 2) = 0, that is substituting value into the polynomial
f(- 1) = (- 1)³ - 2(- 1)² - a + b = 0 , that is
- 1 - 2 - a + b = 0
- a + b = 3 → (1)
f(- 2) = (- 2)³ - 2(- 2)² - 2a + b = 0, that is
- 8 - 8 - 2a + b = 0
- 2a + b = 16 → (2)
Multiply (1) by - 2
2a - 2b = - 6 → (3)
Add (2) and (3) term by term to eliminate a
- b = 10 ( multiply both sides by - 1 )
b = - 10
Substitute b = - 10 into (1) and evaluate for a
- a - 10 = 3 ( add 10 to both sides )
- a = 13 ( multiply both sides by - 1 )
a = - 13