Question

a In triangle ABC, the ine BD is perpendicular to AC
AD=(x+6)cm, DC = (X+2)CM and the height BD=(x+1) cm
The area of triangle ABC is 40cm^2
1) Show that x^2 + 5x -36 = 0
2) Calculate the length of BC

Answer 1

area of a triangle = half the base times the perpendicular height

Answer 2

so the length os the base AC is

Ad + DC = x + 6 + x + 2

so what does that simplify too?