A is the correct answer
Explanation:
If you plug y=x+10 in for the Y variable you just have to solve by multiplying.
1.) It should look like this:
2x + 3(x +10) = 40
2.) You will distribute the three which will make the equation look like this:
2x + 3x + 30 = 40
3.) Add like terms. Then subtract 30 from both sides. Then divide 5 by both sides to get the variable x alone.
but 16.5 is the answer