SOLUTION: A picture frame measures 28 cm by 32 cm and is of uniform width. What is the width of the frame if 192 cm^2 of the picture shows?
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Question 344053: A picture frame measures 28 cm by 32 cm and is of uniform width. What is the width of the frame if 192 cm^2 of the picture shows? Answer by checkley77(12844) (Show Source):
You can put this solution on YOUR website! 28*32=896 in^2
(28-2x)(32-2x)=896-192
896-64x-56x+4x^2=704
4x^2-120x+896-704=0
4x^2-120x+192=0
4(x^2-30x+48)=0
x=(30+-sqrt[30^2-4*1*48])/2*1
x=(30+-sqrt[900-192])/2
x=(30+-sqrt708)/2
x=(30+-26.61)/2
x=(30-26.61)/2
x=3.39/2
x=1.695 inches for the border.
Proof:
(28-2*1.695)(32-2*1.695)=896-192
(28-3.39)(32-3.39)=704
24.61+28.61=704
704=704