Answer:
length = 8x
If the length is 80, the width is 27
Explanation:
The area of the rectangle is 16x^2 + 56x
The width of the rectangle is 2x+7
Area is length times width
16x^2 +56x = (2x+7) * L
Factor an 8x from the left side
8x(2x+7) = (2x+7) *L
Divide each side by (2x+7)
8x(2x+7)/(2x+7) = (2x+7)/(2x+7) *L
8x =L
The Length is 8x
The length is 80
80 = 8x
Divide each side by 8
80 /8 = 8x /8
10 =x
Now we can find the width
w = 2x+7
w = 2(10) +7
w = 20+7
=27