Question

I really need the answers with an explanation..

1.solve the system by substitution

-2.5x+y=13.5
2.25x-y=12.25

A: (-5,1)
B: (-1,5)
C: (1,-5)
D: (5,-1)

2.solve the system using elimination.

2x+6y=-12
5x-5y=10

A: (2,1)
B: (0,-2)
C: (-2,0)
D: (1,2)

3.what is the solution to the following system.

-3x-2y=-12
9x+6y=-9

A: (2,1)
B: no solution
C: (-2,-1)
D: infinitely many solutions

4. what is the solution to the following system.

3x+2y=7
-2x+3/4y=-13

A: (5,4)
B: (-5,4)
C: no solution
D: infinitely many solutions