SOLUTION: Write a system of two equations in two unknowns. Solve the system by using the substitution method. « The length of a rectangular field is 12 feet longer than the width. If the p

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: Write a system of two equations in two unknowns. Solve the system by using the substitution method. « The length of a rectangular field is 12 feet longer than the width. If the p      Log On


   

Question 207161: Write a system of two equations in two unknowns. Solve the system by using the substitution method. « The length of a rectangular field is 12 feet longer than the width. If the perimeter is 144 feet, then what are the length and width
Answer by jojo14344(1513) About Me  (Show Source):
You can put this solution on YOUR website!


First Equation:
L=12%2BW, Length is 12 ft longer than the Width

Second Equation:
P=2L%2B2W
144=2L%2B2W

Substituting L in the 1st Eqn to the 2nd Eqn:
144=2%28blue%2812%2BW%29%29%2B2W
144=24%2B2W%2B2W
144-24=4W ---> 120=4W ---> cross%28120%2930%2Fcross%284%29=cross%284%29W%2Fcross%284%29
highlight%28W=30ft%29

Back in First Equation:
L=12%2B30
highlight%28L=42ft%29

Check via Second Equation:
144=2%2842%29%2B2%2830%29
144=84%2B60
144ft=144ft

Thank you,
Jojo