Answer :
Add the two functions together to get
7y=-3
y=-3/7
Then plug in y to either function to solve for x, I’ll just use the left one
15(-3/7)-9x=-9
-45/7-9x=-9
-9x=-18/7
x=18/7/9
x=2/7
7y=-3
y=-3/7
Then plug in y to either function to solve for x, I’ll just use the left one
15(-3/7)-9x=-9
-45/7-9x=-9
-9x=-18/7
x=18/7/9
x=2/7