The linear combination method is applied to a system of equations as shown.

4(.25x + .5y = 3.75) → x + 2y = 15
1/4 (4x – 8y = 12) → x – 2y = 3
2x = 18
What is the solution of the system of equations?

A.(1,2)
b.(3,9)
c.(5,5)
d.(9,3)