4 number 2 variable problems?

Hello, again. I have done all the 3 number 2 variable problems. However I am having immense problems with the 4 number 2 variable problems.

8-3c=2c-7

I thought

8-3c=2c-7

8-3c-2c=2c-7-2c

8-1c=7

And I'm lost.

Am I doing it wrong?

Any tips for future problems like this?

My attempt on the next problem

8-3c=2c-2

8-3c+3c+2=2c-2+3c+2

10-1c

Stuck again ;(

Do I have my formula or technique wrong?

Do I get the concept now?

I think I am getting closer to getting this, hope I am not too much of bother.

3-4b=10b+10

3-4b+4b+10=10b+10+4b+10

13=14+10

Where exactly did I go wrong?