Remove the parenthises and simplify:

8p+3q-9(8p-5q+9r)

I have gotten lost on this one. Anyone have any ideas? I tried combinging like terms, but I keep getting the wrong answer.

To remove parenthses, you need to apply the law of distributivity, which implies:

a(b+c) = ab + ac
for example:
4(2x-3y)
=4.2x - 4.3y
=8x-12y

You need to apply the above rule to remove the only set of parentheses in the given expression, and group like terms (i.e. terms with the same variable names and power) to get the final answer.
Post your answer if you are not sure.