system of equations

Question

A rectangle has a perimeter of 48 inches. If twice the length decreased by three is equal to three times the width, then find the length.

Answer 1

2L + 2W = 48

 

2L - 3 = 3W

 

 

2L + 2W = 48

 

2L - 3W = 3

 

 

SOLVE THROUGH ELIMINATION (SUBTRACT EQUATONS)

 

5W = 45

 

W = 9

 

If W = 9 then the length must be 

 

2L - 3 = 3(9)

2L - 3 = 27

2L = 30

L = 15