There is one unique solution for this system of equations.
By solving the system of equations simultaneously, we find the value of x and y that satisfies both equations.
First, we substitute y = 5x + 7 into the second equation:
3(5x + 7) - 15x = 18
15x + 21 - 15x = 18
21 = 18
This leads to a contradiction, confirming that there is no solution to this system of equations.