Question

The perimeter of the rectangle below is 74 units. Find the length of side RS

Write your answer without variables.

Answer 1

The answer is 28 if you use the method I used

Answer 2

20 units

Explanation:

The perimeter of a rectangle is

P = 2(l+w)

P = 2( 3x+2 + 4x)

Adding like terms

P = 2( 7x+2)

We know the perimeter is 74 units

74 = 2 ( 7x+2)

Divide by 2

74/2 = 2/2 (7x+2)

37 = 7x+2

Subtract 2 from each side

37-2 = 7x+2-2

35 = 7x

Divide by 7

35/7 = 7x/7

5 =x

We want to find the length RS = PQ = 4x

RS = 4x = 4*5 = 20