The length of a rectangular floor is 5 feet less than twice its width. The area of the rectangle is 150 square feet. What is the length of the room?

1 Answer
Jul 17, 2017

See below

width #= 10# feet
length #= 15# feet

Explanation:

Area = length X width
let width #w=x#
let length #l=2x-5#

#A=150=x(2x-5)#

distribute #" "150=2x^2-5x#

subtract 150 from both sides #" "150-150=2x^2-5x-150#

factor #" "(2x+15)(x-10)=0#

width #x=10" "# or #x=-15/2#
since distance cannot be negative, #" "x=10#

width #= 10# feet
length #= 2*10-5 =15# feet