SOLUTION: What rectangle has an area of 84ft and a perimiter of 40

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Question 1146330: What rectangle has an area of 84ft and a perimiter of 40
Found 2 solutions by ankor@dixie-net.com, MathTherapy:
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
What rectangle has an area of 84ft
L * w = 84
and a perimeter of 40
2L + 2w = 40
simplify, divide by 2
L + w = 20
L = (20-w)
:
in the first equation, replace L with (40-w)
(20-w) * w = 84
A quadratic equation
-w^2 + 20w - 84 = 0
Multiply by -1
w^2 - 20w + 84 = 0
Factors to
(w-6)(x-14) = 0
the smaller solution is the width
w = 6,
find L: 20-6 = 14 is the length

Answer by MathTherapy(10555) About Me  (Show Source):
You can put this solution on YOUR website!

What rectangle has an area of 84ft and a perimiter [sic perimeter] of 40
A rectangle with dimensions: 14 ft by 6 ft