How do you factor #x^2 + 13x + 42#?

1 Answer
Jul 23, 2016

Answer:

#(x+6)(x+7)#

Explanation:

In trying to find the factors, we read from the right to the left.

Find factors of 42 which ADD (+) to give 13.

The + also tell us that both signs will be the SAME, they will both be + (because of +13)

There are several factor pairs of 42:
#1xx42 " sum is" 43#
#2xx21 " sum is" 23#
#3xx14 " sum is" 17#
#6xx7 " sum is" 13 rArr " these are the factors we want" #

#(x+6)(x+7)#