Question 389307
1.
3x-y=7 ----> 6x - 2y = 14, after multiplying by 2.
6x-2y=6
The system is inconsistent.  The lines are parallel.

2. 
3x+2y=5
-x+5y=7
The system is consistent & independent.  (The determinant of the coefficient matrix is non-zero.)  The lines intersect.

3. 
-x-2y=-3 --------> 3x + 6y = 9, after multiplying both sides by -3
3x+6y=9 (The two equations are the same!)
The system is dependent.  The lines are coincident.