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the height of a triangle is 4 inches greater than twice its base. the area of the triangle is 168 square inches. what is the base of the triangle?

Area=1/2 B*H= 1/2 B (2B+4)

solve for B

h = 4 + 2b
b = ?
A = (b*h)/2 = 168

168 = [b(4+2b)]/2
168 = (4b + 2b^2)/2
336 = 4b + 2b^2
2b^2 + 4b - 336 = 0
2(b^2 + 2b - 168) = 0
2(b-12)(b+14) = 0
b=12 and b=-14

Ignore the negative answer, negative distances have no real meaning.

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