How do you factor by grouping #12xy- 8x + 42y - 28#?

1 Answer
May 17, 2015

#12 xy - 8x + 42y -28#

We factor this expression by making groups of 2 terms
#= (12xy - 8x) + (42y - 28)#

Now we take the common factors out from each group
# = 4x( 3y -2) + 14(3y -2)#

#( 3y -2)# is a common factor to each of the terms now:
# = (3y -2)(4x +14)#

#2# is common to the terms in the second group above
# = (3y -2){2(2x+ 7)}#

# color(green)( (3y -2){2(2x+ 7)}# is the Factorised form of #12 xy - 8x + 42y -28#