# Solve the following by using the quadratic formula?

Jul 19, 2016

x =-1 and $x = - \frac{b + c}{a + b}$

#### Explanation:

y = (a + b)x^2 + (a + 2b + c)x + (b + c) = 0
y is in the quadratic form:
y = Ax^2 + Bx + C = 0, with
A = a + b
- B = - a - 2b - c
C = b + c
Since A - B + C = 0, use shortcut:
The 2 real roots of y are: x = - 1 and $x = - \frac{C}{A} = - \frac{b + c}{a + b}$