Question 211295: The base of a triangle is one more than four times the height. Determine the dimensions that will give a total area of 9 cm^2. What is the minimum area of such a triangle?
Answer by RAY100(1637)   (Show Source):
You can put this solution on YOUR website! Let h= height of triangle
let b=base= (4h+1)
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Area = 1/2 *b*h = 1/2 * (4h+1)*h = 2h^2 + 1/2 h
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but Area = 9 = 2h^2 +h/2
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or,,,,0= 2h^2 +h/2 -9,,,,,,,mult by 2
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0= 4h^2 +h - 18
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0 = (4h+9)(h-2)
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h=2,,,,-9/4{not realistic}
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h=2,,,b=9
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check a=1/2 * 2*9 =9,,,,,ok
b=4*2+1=9,,,,,,ok
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