What you're saying doesn't make any sense... Were you given the equations of three lines and asked which triangle they form? If so, you'll need to post all three equations.
There was a question in an objective exam that the three lines form a triangle which is :-
d) Right angle triangle
The equation was in the form :- x + 3y = 4 ; x- y = 5 etc......
My question is that how to find the three vertices using three line equations. ?