Question

A rectangle is 4 times as long as it is wide. The perimeter is 30 feet. Find the dimensions.

Answer 1

Answer: 3 by 3 by 12 by 12

Step-by-step explanation: Two sides are x feet long. The two other sides are 4 times x feet long. 4x+4x+x+x =10x

Set that equal to 30 and solve. x=3

Plug back into the original 4x's and x's to get the lengths

Answer 2

Express your length and width as algebraic expressions:

width = x

length = 4x

Use the formula for the perimeter of a rectangle to solve for x:

perimeter = 2(length) + 2(width)

50 = 2(4x) + 2(x)

50 = 8x + 2x

50 = 10x

5 = x

The width (x) is 5 feet and the length (4x) is 20 feet.

Explanation: