Elliot W. answered 10/12/20
Professional Software Engineer, Tutor, Degree in Computer Science
Well, we know that the perimeter is as follows:
For length L, and width W, Perimeter = L + L + W + W, or Perimeter = 2 * L + 2 * W
We are given that L = W + 4, and that Perimeter = 36 feet.
So, we just need to plug in what we know. First, let's plug the total perimeter into the equation for calculating the perimeter. So we get
Perimeter = 2 * L + 2 * W
36 = 2 * L + 2 * W
Now, let's plug in the other information we know, namely that L = W + 4. Then we can solve for W.
36 = 2 * L + 2 * W
36 = 2 * (W + 4) + 2 * W
36 = 2 * W + 2 * 4 + 2 * W
36 = 2 * W + 8 + 2 * W
36 = 2 * W + 2 * W + 8
36 = 4 * W + 8
-8 -8
28 = 4 * W
/4 /4
7 = W
So, now we have solved for W! We can get L from the given statement that L = W + 4 by plugging in our new value for W.
L = W + 4
L = 7 + 4
L = 11
Let's check with the other equation. We now have W = 7, L = 11, Perimeter = 36, and Perimeter = 2 * L + 2 * W. Let's plug all that information in.
Perimeter = 2 * L + 2 * W
36 = 2 * L + 2 * W
36 = 2 * 11 + 2 * 7
36 = 22 + 14
36 = 36
Wonderful, it all checks out! So, we have found and confirmed that the width of our rectangle is 7 and the length of our rectangle is 11!