<PRE><B>Question 859354</B>
let base be x
height = 2x+3

area = 1/2 * b * h

15= 1/2 * x* (2x+3)

30 = x(2x+3)

30 = 2x^2+3x

2x^2+3x-30=0

solve for x the base

x= 3.2


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