# Thread: Just a quick question...

1. ## Just a quick question...

Can anyone check this over for me? I did something wrong, but I'm not sure what it is...

Expand, Then simplify:

3(2m-4n+3)-5(-2m+5n-1) --->(6m-12n+9)-(10m-25+5)

(This is the part where I simplified)---> -4m-37n+5 (???)

In the textbook, the correct answer is 16m-37n+14...help?

2. Originally Posted by May_18
Can anyone check this over for me? I did something wrong, but I'm not sure what it is...

Expand, Then simplify:

3(2m-4n+3)-5(-2m+5n-1) --->(6m-12n+9)-(10m-25+5)

(This is the part where I simplified)---> -4m-37n+5 (???)

In the textbook, the correct answer is 16m-37n+14...help?
the line in red is wrong

note you have a negative sign outside the brackets, which when expanded will give you a -10m for the first term. however, -5*-2m = +10m

prevent this mistake form happening again: remove the brackets when you expand! that way, you can correctly see what terms should have what sign

3. OH! *smacks self on forehead* How could I forget? Thank you very much for the help! I really appreciate it!