Answer:
A: 3x + 14x + 4y - 7 + 2
Explanation:
Lets look at A. First add like terms. 3x + 14x is 17x. We also have 17x in the nain equation, so we know that they both have 17x in them. There is also a 4y in both equations, so we know it works so far. -7 + 2 is -5, both equations have a -5, so we know A works!
Lets look at B. 17x and -5 are there in both equations. Lets add 2y - 2y. It equals 0. 0 and 4y are not equal, so B does not work.
Lets look at C. Both equations have 4y and -5 in them. In C the 17x is negative, while in the main equation 17x is positive, so we know C does not work.
A is the answer, I hope this helps you! Let me know if I got anything wrong or you need me to explain things further.