so, you would replace the variables with the numbers. it would be 6 - 6 + 4, then you would just add/subtract as normal. the answer, how i got it, would be 4.
If A=6 then you would have to plug that in for a which would become 6-6 which equals 0.Then you would have to plug in 4 for b so you would do 0+4= your answer of 4.
