SOLUTION: The length of a rectangle is 18 cm less than five times its width. Its area is 35 square cm. Find the dimensions of the rectangle.

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Question 967003: The length of a rectangle is 18 cm less than five times its width. Its area is 35 square cm. Find the dimensions of the rectangle.
Answer by Timnewman(323) About Me  (Show Source):
You can put this solution on YOUR website!
from your question,
L=5w-18-----(1)
where L=lenght,
w=width
but,L*w=35----(2)
put equ 1 in 2
(5w-18)w=35
5w²-18w-35=0
factorize the quadratic equation and get:
(5w-7)(w-5)=0
5w-7=0 or w-5=0
5w=7 or w=5cm
w=7/5cm
substitute for w in equ 1
L=5(5)-18
L=25-18
L=7cm
or L=5(7/5)-18
=7-18
=-11cm
now,when w=5cm,L=7cm
when w=7/5cm,L=11cm