Big Ideas Math Geometry, 2014
BI
Big Ideas Math Geometry, 2014 View details
Maintaining Mathematical Proficiency
Continue to next subchapter

Exercise 4 Page 591

Use the formula for perimeter of a rectangle.

9 inches

Practice makes perfect
A rectangle has two pairs of equal sides, so we can find its perimeter using the following formula. P=2l+2w In this formula l is the length and w is the width. We know that P is equal to 28 inches and that w is equal to 5 inches. By substituting these values into the formula we can calculate l.
P=2l+2w
28 =2l+2 ( 5)
Solve for l
28 = 2 l + 10
18 = 2 l
2 l = 18
l = 9
The length of the rectangle is 9 inches.