Two lines, R and M, are represented by the following equations:

Line R: 2x + 2y = 18
Line M: x + y = 9

Which statement is true about the solution to the set of equations? (4 points)

Select one:
a. It is (18, 9).
b. It is (9, 18).
c. There are infinitely many solutions.
d. There is no solution