By solving a system of equations, we will see that the correct option is:
"length is 8 in, width is 5 in"
How to find the system of equations?
First, we know that for a rectangle of width W and length L the area is given by:
A = L*W
Here we know that:
L = 2*W - 2in
A = 40 in^2 = L*W
That is or system of equations, to solve it, we replace the first equation into the second one.
40 in^2 = (2W - 2in)*W
40 in^2 = 2W^2 - 2in*W
2W^2 - 2in*W - 40 in^2 = 0
This is a quadratic equation, the solutions are given by the Bhaskara's formula:
[tex]W = \frac{(2in) \pm \sqrt{(-2in)^2 - 4*2*(-40in)} }{2*2} \\\\W = \frac{(2in) \pm 18in }{4}\\[/tex]
We only care for the positive solution, so we have:
W = (2in + 18in)/4 = 5in
Then:
L = 2*W - 2in = 2*5in - 2in = 8in
The correct option is:
"length is 8 in, width is 5 in"
If you want to learn more about systems of equations, you can read:
https://brainly.com/question/13729904
