Answer:
w = 6
Explanation:
Givens
Area = 90
Let the width = w
Let the length = 2w + 3
Formula
Area = L * W
Solution
Area = (2w + 3)*w
Area = (2w + 3)* w = 90 Remove the brackets.
Area = 2w^2 + 3w = 90 Subtract 90 from both sides.
2w^2 + 3w - 90 = 0
This will factor into
(w - 6)(2w + 15) = 0
Only w - 6 will = a zero that makes sense when speaking of an area
w - 6 = 0
w = 6
L = 2*w + 3
L = 2*6 + 3
L = 15
The width is 6