SOLUTION: a rectangular table top has a perimeter of 26 inches and an area of 40 square inches find the dimensions

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Question 715443:
a rectangular table top has a perimeter of 26 inches and an area of 40 square inches find the dimensions
Answer by checkley79(3341) About Me  (Show Source):
You can put this solution on YOUR website!
P=2L+2W
26=2L+2W
A=LW
40=LW
L=40/W
26=2(40/W)+2W
26=80/W+2W
26=(80+2W*W)/W
26=(80+2W^2)/W CROSS MULTIPLY.
26W=80+2W^2
2W^2-26W+80=0
2(W^2-13W+40)=0
2(W-5)(W-8)=0
W-5=0
W=5 ANS. L=8 ANS.
W-8=0
W=8 ANS. L=5 ANS.
PROOF:
40=5*8
40=40
26=2*5+2*8
26=10+16
26=26