THIS USER ASKED 👇

Solve the system of equations 3y + 2z = 12 and y – z = 9.
A. y = –6, z = 15 C. y = 6, z = –3
B. y = 24, z = 15 D. y = 6, z = 15

THIS IS THE BEST ANSWER 👇

3y + 2z = 12 (equation 1) y – z = 9, multiply 2 on both sides: 2y – 2z = 18 (equation 2) Putting up equations 1 and 2 we find: 5y = 30, y = 30/5 = 6; 6 – z = 9, z = 6 – 9 = -3 The solution for the system of equations 3y + 2z = 12 and y – z = 9 is C. y = 6, z = –3.