
Shelley J. answered 03/02/16
Tutor
New to Wyzant
English, Math and Test Prep Tutor
This problem can be solved by setting up 2 equations:
- The first equation is the area of the rectangle. L * W = Area --> In this case the equation is L * W = 35
- The second equation deals with relating length and width based on the information in the problem, so L = W + 2
No substitute the length equation (equation 2) into the area equation (equation 1), which gives you (W + 2) * W= 35.
When multiplying by W, we get 2W + W2 = 35. By subtracting 35 from both sides we now have an equation that can be factored.
W2 + 2W - 35 = 0
(W - 5)(W+7) = 0
Now we set each equal to zero to solve for W.
W - 5 = 0
W = 5
W + 7 = 0
W = -7 [since the width of a rectangle cannot be negative, we know that the width is 5]
Knowing that the width of the rectangle is 5, we can now plug this answer into the area equation (equation 1) to find the length.
L * 5 = 35
L = 7