How do you simplify 1/3(15a+9b)-1/7(28b-84a)?

1 Answer
Jan 24, 2017

See the entire simplification process below

Explanation:

First, expand the terms in parenthesis by multiplying the by the terms outside their respective parenthesis:

color(red)(1/3)(15a + 9b) - color(blue)(1/7)(28b - 84a) ->

(color(red)(1/3) xx 15a) + (color(red)(1/3) xx 9b) - (color(blue)(1/7) xx 28b) + (color(blue)(1/7) xx 84a) ->

5a + 3b - 4b + 12a

Next, group like terms:

5a + 12a + 3b - 4b

Now. combine like terms:

(5 + 12)a + (3 - 4)b

17a - 1b

17a - b