SOLUTION: Find the dimensions of a rectangle whose area is 156 cm2 and whose perimeter is 50 cm.

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Question 1145660: Find the dimensions of a rectangle whose area is 156 cm2 and whose perimeter is 50 cm.
Found 2 solutions by Alan3354, ikleyn:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Find the dimensions of a rectangle whose area is 156 cm2 and whose perimeter is 50 cm.
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L*W = 156
L + W = 25
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Find a pair of factors of 156 that add to 25.
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Hint: They're integers.

Answer by ikleyn(52786) About Me  (Show Source):
You can put this solution on YOUR website!
.
x + y = 50/2

xy    = 156


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x + y = 25

xy    = 156


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x = 25 - y

y*(25-y) = 156

y^2 - 25y + 156 = 0


y%5B1%2C2%5D = %2825+%2B-+sqrt%2825%5E2+-+4%2A156%29%29%2F2 = %2825+%2B-+sqrt%281%29%29%2F2 = %2825+%2B-+1%29%2F2.


There are 2 roots,  y= 13  and  y= 12.


ANSWER.  The dimensions of a rectangle are 12 cm and 13 cm.