Skip to content
Factoring Polynomials
Example 4

Example 4: Factoring Quadratics

Step-by-step worked example for this lesson track.

Problem

Larger root of x2+15x+54=0 is ?\text{Larger root of }x^2+15x+54=0\text{ is }?

1. Recognize Pattern

x2+bx+c=(xr1)(xr2),  r1+r2=b,  r1r2=cx^2+bx+c=(x-r_1)(x-r_2),\;r_1+r_2=-b,\;r_1r_2=c

2. Apply Method

x25x50=(x10)(x5)x^2-5x-50=(x-10)(x--5)

3. Conclude

x{6,9}x\in\left\{-6,-9\right\}

Final answer

x{6,9}x\in\left\{-6,-9\right\}