### Home > GB8I > Chapter cc46 > Lesson cc46.1.1 > Problem 6-12

6-12.

Solve this problem by writing and solving an equation. Be sure to define your variable. Does your answer make sense in this context? Homework Help ✎

A rectangle has a perimeter of 30 inches. Its length is one less than three times its width. What are the length and the width of the rectangle?

Set up two equations:

3*W* − 1 = *L*

2*W* + 2*L* = 30

Substitute (3*W* − 1) for *L* and solve the equation:

2*W* + 2 (3*W* − 1) = 30

Width is 4 inches and length is 11 inches.