Question

The area of a triangle is 17.5 square meters. The height of the triangle is 3 meters less than twice its base. The base of the triangle is x meters. Complete the equation that represents this description and fill in the values for the base and height of the triangle. The equation modeling the described triangle is x2 + x + = 0. The base of the triangle is meters. The height of the triangle is meters.

Answer 1

A = ½ * base * height

A = ½ * x * (2x-3)

17.5 = ½ * (2x² - 3x)

35 = 2x² - 3x

0 = 2x² - 3x - 35

2x² - 3x - 35 = 0 .......... (the equation)

(2x + 7)(x - 5) = 0

2x + 7 = 0

2x = - 7

x = -7/2 = -3.5

x-5 = 0

x = 5

since we have two result of x, then we can choose the positive one x = 5

so the base is 5 m and the height is

h = (2x - 3) = 2*5 - 3 = 10-3 = 7 m