Ok so I’m not sure but this is how we solve it in the way I learned.
-You add and simplify the equation first so it will be
2c + 20(3) = 120
2c + 60 = 120
-Then you subtract the 60 by itself and then the 120 and it leaves you with
2c = 60
-lastly you divide
2c/2 = 60/2
Then you find your answer is 30
C = 30
