Remove parentheses and simplify 7a+6b-4 (3a-3b)

Normally, you would do whatever is inside of the parenthesees first then do the rest but we cant get any further so we remove the parenthasees by distrubtion

7a+6b-4 (3a-3b)

-4 (3a-3b)

a (b+c) = (ab) + (ac)

-4 (3a-3b) = - 12a - (-12b)

7a+6b-12a+12b

7a-12a+6b+12b

-5a+18b

that's the asnwer