Irene R. answered 09/12/19
Senior Mechanical Engineer with 13+ years of Teaching Experience
First, remember that perimeter is equal to the distance around a rectangle. That means that the perimeter (p) is equal to 2 times the width (w) plus 2 times the length (l). so an equation for perimeter is
p= 2l + 2w
For this problem, we know that numerical value of the perimeter:
56 = 2l + 2w
Since we know that the length is 4 more than twice the width, we can represent the length l with this expression: 4 + 2w
Now our perimeter equation becomes:
56 = 2 (4 + 2w) + 2w
Using the distributive property, we can write
56 = 8 + 4w + 2w
Combining like terms gives us:
56 = 8 +6w
We can solve this equation using inverse operations (i.e. subtract 8 from both sides , then divided both sides of the equation by 6):
56 - 8 = 8 + 6w - 8
48 = 6w
48/6 = 6w/6
8 feet = w