Hi, I am in a linear algebra class, and I don't understand how to work through this problem.

"Consider the linear system below, where a and b represent numbers"

2x - 3y = a

-4x+6y = b

(a) Find the particular values for a and b which make the system consistent.

(b) Find the particular values for a and b which make the system inconsistent.

(c) What relation between the values of a and b implies the system is consistent.

When I try to solve the system with elimination, both of the x and y variables disappear on the first step. Not sure what to do.