Solve the system of equations.
3x-y=2
x+3y=19
Find x from the second one x=19-3y
Plug it in the first one 3(19-3y)-y=2
57-9y-y=2
55=10y
Y=5.5
Now find x:
x=19-3*5.5=2.5
So, the coordinates of p is (2.5,5.5), since this is the point that is on both lines.