## anonymous one year ago Can someone help me with this problem? I thought that you were just supposed to subtract "a-4" from the original problem to result in, 3a-12 but that is incorrect it says. Subtract "a-4" from "4a+16" and simplify your answer. The variable "a" should appear only once in your answer.

1. anonymous

Problem with signs. Your idea is correct what happens when you subtract -4 from 16. $16-\left( -4 \right) = ?$

2. anonymous

I guess

3. anonymous

but how should I solve the problem

4. anonymous

All that I know is that 3a+12 is incorrect

5. anonymous

$\left( 4a+16 \right) - \left( a-4 \right) = 4a+16-a+4 = ?$What do you get?

6. anonymous

3a+20?

7. anonymous

Correct. Good job. Do you understand where you went wrong the first time?

8. anonymous

Yes I did not correctly follow the second step, the conversion between (a-4) and a+4 thankyou

9. anonymous

You're welcome.