In this applet we are trying to investigate what we can learn about the coordinates of the point where two straight lines cross on a graph (if they do cross!).
We can vary Line 1 by changing values A, B and C. Similarly we can move Line 2 by varying D, E and F. Try it.

As you vary the lines, notice what happens to the crossing point. Is there always a crossing point? Also, try to use algebra to check that you get the correct values for x and y when you solve Line 1 and Line 2 as simultaneous equations.
The connection between the algebra and the geometry is a vital area of exploration. Enjoy yourself!