Question

The roots of the equation x^2+bx+x=0 are -4 and 2.
Find B and C

Answer 1

b = 2, c = - 8

Explanation:

Given x = a is a root then (x - a) is a factor

Here the roots are x = - 4 and x = 2 , then the corresponding factors are

(x + 4) and (x - 2)

The equation is then the product of the factors , that is

(x + 4)(x - 2) = 0 ← expand factors using FOIL

x² + 2x - 8 = 0

with b = 2 and c = - 8