SOLUTION: a triangle has area 42cm^2. find the height, in cm, if it is 5cm shorter than the base.

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Question 760439: a triangle has area 42cm^2. find the height, in cm, if it is 5cm shorter than the base.
Answer by Cromlix(4381) About Me  (Show Source):
You can put this solution on YOUR website!
Base = x
Height = (x - 5)
Area = 1/2 (base * height)
42 = 1/2 (x*(x - 5))
42 = 1/2(x^2 - 5x)
84 = x^2 - 5x
x^2 - 5x - 84
(x - 12)(x + 7) = 0
x = 12
x = -7 (no answer)
Base = 12cm
Height = 7cm