Answer:
x = -2
y = 5
Step-by-step explanation:
Given two equations
1. 7x + 10y = 36
2. y = 2x + 9
Substitute 2x + 9 for y in equation 1.
We have
7x + 10y = 36
7x + 10(2x + 9) = 36
Distribute 10 into (2x + 9)
We have
7x + 10 x 2x + 10 x 9 = 36
7x + 20x + 90 = 36
27x + 90 = 36
Subtract 90 from both sides to eliminate 90 on the left side
27x + 90 - 90 = 36 - 90
27x = -54
Divide both sides by 27 to isolate x
27x/27 = -54/27
x = -2
Now substitute -2 into either equation to get y
Using equation 2, we have
y = 2x + 9
= 2 x -2 + 9
= -4 + 9
= 5
x = -2
y = 5
Check
7(-2) + 10(5) = 36
Its D
Because the rate of change is 1.5 and 1.5x10 is 15
<h2>The test is worth 15 points.</h2><h3 /><h3>Double-check:</h3><h3>15 x 1.2 = 18</h3>
First row is 3 cookies for every $1, proportional, and Table to the right
Second row is 3 more cookies than donuts, non-proportional, and the Table on the left
