Question

Each end of a glass prism is a triangle with a height that is 1 inch shorter than twice the base. If the area of the triangle is 60 square inches, how long are the base and height?

Answer 1

Explanation:

Let the base = x inches

So, h = 2x - 1

Area of triangle = 60 square inches

(1/2) * base *height = 60

(1/2) * x * (2x-1) = 60

x *(2x-1) = 60*2

2x² - x = 120

2x² - x - 120 = 0

2x² - 16x + 15x - 15*8 = 0

2x ( x - 8) + 15 (x -8) = 0

(x-8) (2x + 15 ) = 0

x- 8 = 0 {ignore 2x +1 as it will give negative value}

x = 8

Base = 8 inches

Height = 2*8 - 1 16 - 1 = 15 inches