SOLUTION: A rectangle is 8 cm longer than it is wide. Find the dimensions of the rectangle if its area is 240 sq-cm. length = cm width = cm

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Question 278296: A rectangle is 8 cm longer than it is wide. Find the dimensions of the rectangle if its area is 240 sq-cm.
length = cm
width = cm
Found 2 solutions by Grinnell, mananth:
Answer by Grinnell(63) About Me  (Show Source):
You can put this solution on YOUR website!
x+8 is length
x is width, OK
x(x+8)=240
x^2+8x=240
x^2+8x-240=0
(x+20)(x-12)=0
X cannot be negative, so x must be 12.
SO, 20 is length
12 is length
Don't be afraid of quadratic equations!!!! Do the WORK!! LOL Good night.

Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
Let the width be x
length = x+8
x(x+8) =240
x^2+8x=240
x^2+8x-240=0
x^2 +20x-12x-240=0
x(x+20)-12(x+20)=0
(x+20)(x-12)=0
x=-20 0r 12
12, and 20