The length of a rectangle is 5 inches longer than the width.The perimeter of the rectangle is 40 inches.What is the width of the rectangle, in inches?

Answer 1

We know the length (5 in. longer than the width, and the perimeter (distance around the rectangle. So, solving this algebraically is pretty straight forward.

w = width (unknown)

l = length (width + 5 in.)

p = perimeter (40 in.)

equation

w + w + 5 = 40

We have two w's, so we start by simplifying this term. Now we have 2w (w + w) and continue to equation.

2w + 5 = 40

Move the 5 to the other side by subtracting from both sides:

2w + (5 - 5) = 40 - 5

2w = 35

Now, divide both sides by 2 (to separate the number from the variable). The answer is:

w = 17.5 inches

To check if the answer is correct, just insert 17.5 into the original equation where there's a w.

17.5 + 17.5 + 5 = 40

35 + 5 = 40

40 = 40

I hope this helps.

Answer 2

L=5+W

40 = 2L + 2W = 2(5+W) + 2W = 10+2W +2W = 10+4W

4W = 30

W = 30/4 = 7 1/2 inches wide

L = 12 1/2 inches long