SOLUTION: The altitude of a triangle is 5 m less than its base. The area of the triangle is 80 mē. Find the base.

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Question 1031847: The altitude of a triangle is 5 m less than its base. The area of the triangle is 80 mē. Find the base.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The altitude of a triangle is 5 m less than its base. The area of the triangle is 80 mē. Find the base.
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Area = (1/2)base*altitude
80 = (1/2)b*(b-5)
160 = b^2 - 5b
b^2 - 5b - 160 = 0
Use the quadratic formula to get::
b = [5 +- sqrt(25-4*-160)]/2
Positive solution::
b = [5 + sqrt(665)]/2
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b = 30.78/2
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base = 15.39 meters
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Cheers,
Stan H.
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