SOLUTION: Find the point of intersection of the two lines x+3y=1 and x-3y=5

For it, solve the system

x + 3y = 1,   (1)
x - 3y = 5.   (2)

To solve it, add the equations (both sides). You will get

2x = 1 + 5  --->  2x = 6  --->  x =  = 3.

Then from (1)  3y = 1 - x  --->  3y = 1-3 = -2  --->  y = .

Answer.  (x,y) = (3,).