Question 476973: A picture 18 cm by 15 cm, has a uniform frame around it. If the area of the frame is 234 cm , find the dimension of the frame.
Answer by lwsshak3(11628)   (Show Source):
You can put this solution on YOUR website! A picture 18 cm by 15 cm, has a uniform frame around it. If the area of the frame is 234 cm , find the dimension of the frame.
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let x= width of frame
width of frame with picture=15+2x
length of frame with picture=18+2x
Area of frame with picture=(18+2x)(15+2x)=(270+66x+4x^2)
Area of picture alone=18*15=270
Area of frame with picture-Area of picture alone=234
270+66x+4x^2-270=234
4x^2+66x-234=0
2x^2+33-117=0
(x-3)(2x+39)
x=3 cm
or
x=-39/2=-19.5(reject, x>0)
ans:
Width of frame= 3 cm with outside dimensions 21 by 24 cm
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