Write equations for three lines that intersect to form a triangle

1.
Any 3 lines a, b and c intersect and form triangles, in no 2 of them are parallel.

2.

2 lines are parallel only if their slopes are equal.

3.

if the equation of a line l is given in the form y=mx+t, then m, the coefficient of x, is the slope of that line.

4.

so given lines a, b, c with equations: 



if , then the lines intersect, forming thus a triangle.

5.

let the 3 lines be: