Linear equations substitution
For example, y=x+4 and y=5x+2.That would mean that x+4=y=5x+2.Simplify it to x+4=5x+2.x=5x-2-4x=-2x=1/2.Now, plug x into one of the equations.y=x+4y=1/2+4y=9/2.Therefore, the POI is (1/2,9/2).