Eugene E. answered • 11/09/17

Math Tutor for High School and University Students

Let b denote the base (in inches) of the triangle. Then the height is b - 2. The area of a triangle is 1/2 x (base) x (height), so

(1/2)b(b - 2) = 40

b(b - 2) = 80

b^2 - 2b = 80

b^2 - 2b - 80 = 0

(b - 10)(b + 8) = 0

b = 10, -8

Since b cannot be negative, b = 10in. Therefore, h = b - 2 = 8in.