SOLUTION: A picture measuring 40cm by 60cm is surrounded by a frame of uniform width. If the area of the frame equals the area of the picture,then what is the width of the frame ? Pleas

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Question 118768:
A picture measuring 40cm by 60cm is surrounded by a frame of uniform width. If the area of the frame equals the area of the picture,then what is the width of the frame ?
Please help me :)
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
40*60=2400 CM^2 FOR THE AREA OF THE PICTURE.
2400+2400=4800 IS THE AREA OF THE PICTURE & THE FRAME.
(40+2X)(60+2X)=4800
2400+120X+80X+4X^2=4800
4X^2+200X+2400-4800=0
(4X^2+200X-2400)=0
4(X^2+50X-600)=0
4(X+60)(X-10)=0
X-10=0
X=10 CM IS THE WIDTH OF THE FRAME.
PROOF
(40+20)(60+20)=4800
60*80=4800
4800=4800