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The length of a rectangle is three times its width and its perimeter is 120 feet.

What are the dimensions?

2 Answers

5 votes

Answer:

45 feet and 15 feet are the length and width

Explanation:

P = 120 feet

a (length) = 3 * b (width)

P = 2 * (a + b)

P = 2 * (3b + b)

P = 2 * 4b

P = 8 * b

=> 8b = 120 feet

P = 120 feet

b = 120 / 8

b = 15 feet

a = 3 * b

a = 3 * 15

a = 45 feet

User Stefano Falasca
by
6.5k points
3 votes

Answer: Width = 45 feet; Length = 15 feet;

Step-by-step explanation: Start by substituting 3w for the length because it says that in the problem. We know that 2(L+W) equals the perimeter. Since we substituted 3w for length we get 8w for the perimeter. Divide 120 by 8 to find that the width is 15 feet and plug it into 3w to get the length of 45 feet.

User Alvits
by
7.7k points