Answer
x=-2 and y=-3
Step-by-step explanation:
Step: Solvey=5x+7for y:
Step: Substitute5x+7 for y in 3x+y=−9:
3x+y=−9
3x+5x+7=−9
8x+7=−9(Simplify both sides of the equation)
8x+7+−7=−9+−7(Add -7 to both sides)
8x=−16
8x/8=−16/8
(Divide both sides by 8)
x=−2
Step: Substitute−2 for x in y=5x+7:
y=5x+7
y=(5)(−2)+7
y=−3(Simplify both sides of the equation)
Answer:
D-2
Step-by-step explanation:
You can use elimination to get the value of y. Move numbers to one side and x and ys to the other side. To use elimination, multiply the first equation with 2. You will get 2x+2y=24. add it with the equation below. y will be eliminated and you will get the value of x. X=10. Plug in x and get the y value. Y=2
Step-by-step explanation:
side ratio = big/small = 28/4 = 7
perimeter ratio = side ratio = 7
-> perimeter ratio = big / small = big/34 = 7
-> big perimeter= 7*34 = 238
Answer:
Natalia's work is wrong.
Step-by-step explanation:
Natalia divided a decimal number by an entire number. Since division is a operation derived from multiplication, the best approach to check if work was good is multiplying the given result by denomination, that is:
1) 
Given.
2) 
Definition of addition.
3) 
Distributive property.
4) 
Definitions of multiplication and decimal number.
5) ![x = 72 +[2\cdot (10)^{-1}]\cdot 12](https://tex.z-dn.net/?f=x%20%3D%2072%20%2B%5B2%5Ccdot%20%2810%29%5E%7B-1%7D%5D%5Ccdot%2012)
Definition of division/Associative property.
6) ![x = 72 + [2\cdot 12]\cdot (10)^{-1}](https://tex.z-dn.net/?f=x%20%3D%2072%20%2B%20%5B2%5Ccdot%2012%5D%5Ccdot%20%2810%29%5E%7B-1%7D)
Associative property.
7) 
Definition of multiplication.
8) 
Definition of divsion.
9) 
Defintion of decimal number.
10) 
Definition of addition/Result
Natalia's work is wrong.
Simplify 3x × 2 to 6x
6x - x + 8y + 4x × 2 - 3x - 5y
Simplify 4x × 2 to 8x
6x - x + 8y + 8x - 3x - 5y
Simplify
<u>10x + 3y</u>
