Quadratic equations, :)

Question

a triangle has a base of 2x+3 and a height of 7x-4. What are the base and height dimensions of the triangle if it has an area of 275m^2

Answer 1

Area = 275 = (1/2)bh = (1/2)(2x+3)(7x-4) = (1/2)(14x^2 +21x -8x -12)

14x^2 +13x -12 = 550

14x^2 + 13x -550 = 0

x = -13/28 + (1/28)sqr(169+4(14)(550) = -13/28 + 6.285 = about 5.9

base = 2x+3 = 14.8

height = 37,3