subtract (-8a+7b-c)-(-9b+3c-5d) when I have a problem with a negative sign before a term that is inside of parentheses don't I have to switch all the signs in those parentheses?

Question

anonymous · Answer

yes you are right

anonymous · Answer

-9c will turn into 9c 
3c will turn into -3c 
and so on

anonymous · Answer

okay so then I can change those signs and then re-distribute to collect like terms correct?

anonymous · Answer

for instance I can add 9b to 7b even though they are in different parentheses or is that wrong?

anonymous · Answer

@romero is this right or am I mistaken?

anonymous · Answer

no you are right. 
these is an example of when you don't add because they are not like terms

4x^2 and 4x

x^2 and x are not like terms

3x and 4x are like terms so you can add them

anonymous · Answer

oh okay thank you, you are a life saver!