SOLUTION: Can someone please show me how to solve A poster is in the shape of a right triangle with a base that is three feet longer than the height. If the area of the triangle is 90 sq

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Question 411655: Can someone please show me how to solve
A poster is in the shape of a right triangle with a base that is three feet longer than the height. If the area of the triangle is 90 square feet, find the height.
a. 9'
b. 12'
c. 15'
d. 18'

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A poster is in the shape of a right triangle with a base that is three feet longer than the height.
Let the height be "x".
Then the base is "x+3".
----
Area = (1/2) base * height
90 = (1/2)(x+3)x
180 = x(x+3)
x^2+3x-180 = 0
(x-12)(x+15) = 0
Positive solution:
x = 12 feet (height)
Cheers,
Stan H.
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If the area of the triangle is 90 square feet, find the height.
a. 9'
b. 12'
c. 15'
d. 18'