How do you combine #4( 3a - b ) - 5( 2a - 3b )#?

1 Answer
Jul 27, 2017

See a solution process below:

Explanation:

First, expand the terms within parenthesis by multiplying each term within the parenthesis by the term outside the parenthesis. Be careful to handle the signs of the individual terms carefully:

#color(red)(4)(3a - b) - color(blue)(5)(2a - 3b) =>#

#(color(red)(4) xx 3a) - (color(red)(4) xx b) - (color(blue)(5) xx 2a) - (color(blue)(5) xx -3b) =>#

#12a - 4b - 10a - (-15b) =>#

#12a - 4b - 10a + 15b#

Next, group like terms:

#12a - 10a - 4b + 15b#

Now, combine like terms:

#(12 - 10)a + (-4 + 15)b#

#2a + 11b#