f(x)=2x^+x-21

Question

x= ___(smaller Value)
x= ___(Larger Value)

What am I doing wrong?
f(x)=0
2x^+x-21=0
(2x+21)(x-19)=0

2x=-21
x=19

Answer 1

You need to factor the end terms. -21 = -7 * 3 or -3 * 7.

The x^2 term factors into 2 and 1.

Which combination will give 1x as a middle term?