The area of a rectangle is 66 ft2 , and the length of the rectangle is 7 ft less than three times the width. Find the dimensions of the rectangle.

Question

No sure how to set this problem up and would like help on how to do it!

Answer 1

w=width

3w=three times the width

3w-7=7 less than three times the width

the length l=3w-7

A=lw

66=(3w-7)(w)

66=3w²-7w

3w²-7w-66=0

factor

3=3*1 and 66=6*11, 6*3=18, 11*1=11, 18-11=7

(3w   )(w   )=0 so far...

(3w   )(w  6)=0 so far...

(3w   11)(w   6)=0 so far...

(3w+11)(w-6)=0

w-6=0

w=6

3w=3*6=18

3w-7=3*6-7=18-7=11

w=6 feet

l=11 feet