SOLUTION: The base of a triangle is 6m greater than twice the height. The area is 28m. Find the height.

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Question 201108: The base of a triangle is 6m greater than twice the height. The area is 28m. Find the height.
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Start with the formula for tha area of a triangle:
A+=+%281%2F2%29bh Substitute: A = 28, b = 2h+6.
28+=+%281%2F2%29%282h%2B6%29h Simplify.
28+=+%281%2F2%29%282h%5E2%2B6h%29 Perfom the indicated multiplication on the right side.
28+=+h%5E2%2B3h Subtract 28 from both sides.
h%5E2%2B3h-28+=+0 Solve by factoring.
%28h%2B7%29%28h-4%29+=+0 so...
h%2B7+=+0 or h-4+=+0 then...
cross%28h+=+-7%29 or highlight%28h+=+4%29 Discard the negative solution as the height, h, can only be positive.
The height is 4 meters.