How do you factor completely #5x^2 - 23 x + 12#?

1 Answer
Mar 17, 2016

Answer:

Use an AC method and factor by grouping to find:

#5x^2-23x+12=(5x-3)(x-4)#

Explanation:

We can use an AC method.

Look for a pair of factors of #AC = 5*12 = 60# with sum #B=23#.

The pair #20, 3# works.

Use this pair to split the middle term and factor by grouping as follows:

#5x^2-23x+12#

#=5x^2-20x-3x+12#

#=(5x^2-20x)-(3x-12)#

#=5x(x-4)-3(x-4)#

#=(5x-3)(x-4)#