How do you factor #5x^2 - 22x - 15 = 0#?

1 Answer
May 25, 2018

#(5x+3)(x-5)# are the factors

Explanation:

Find factors of #5 and 15# whose products subtract to make #22#

#" "5" "3" " rarr 1 xx3 = 3#
#" "1" "5" "rarr 5xx5 = ul25#
#color(white)(xxxxxxxxxxxxxxxxx) 22#

There are the correct factors, now add in the signs to make #-22#

#" "5" "+3" " rarr 1 xx+3 = +3#
#" "1" "-5" "rarr 5xx-5 = ul(-25)#
#color(white)(xxxxxxxxxxxx.xxxxxxxx) -22#

#(5x+3)(x-5)# are the factors