Solve 3x-x+2=12
a) -5
b) 4
c) 7
d) 5

First add the common factors, in this case 3x and -x to get 2x, now subtract 2 from both sides to leave x by itself and you will get 2x=10,now divide by 2 to get x isolated and you will get x=5

Hope this helps

The answer is a 5/20 because if u add all of the marbles there are 20 and there are 5 red marbles so 5/20 is the answer mark as brainliest