I need some algebra help, specifically on literal equations.

I have a feeling it’s really easy, once I know the method.

Here is one of the equations:
x + a = yb
According to the answer sheet, the answer is (yb)/b

Here is another:
ab + c = 5
Answer: ab – ab + c = 5 – ab

Can someone spell out the steps for me? In the first one…what happened to the x + a?
In the second, what happened to the c?