SOLUTION: A mirror 2 feet by 6 feet is to be mounted on a door so that there is a uniform edge between the mirror and the door all around the mirror. How wide will the edge between the mirro
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-> SOLUTION: A mirror 2 feet by 6 feet is to be mounted on a door so that there is a uniform edge between the mirror and the door all around the mirror. How wide will the edge between the mirro
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Question 251272: A mirror 2 feet by 6 feet is to be mounted on a door so that there is a uniform edge between the mirror and the door all around the mirror. How wide will the edge between the mirror and the door be if the area of the edge is 9 square feet? Answer by checkley77(12844) (Show Source):
You can put this solution on YOUR website! 2*6=12 ft^2 is the area of the mirror.
(2+2x)(6+2x)=12+9
12+16x+4x^2=21
4x^2+16x+12-21=0
4x^2+16x-9=0
(2x-1)(2x+9)=0
2x-1=0
2x=1
x=.5 ft. is the width of the edge between the morror & the door edge.
Proof:
(2+2*.5)(6+2*.5)=12+9
(2+1)(6+1)=21
3*7=21
21=21
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