Enter the simultaneous equations you wish to solve by entering the two lines in standard form:

Try this: put in any 3 consecutive numbers in the equations. Like

3x + 4y = 5 and 9x + 10y = 11

Where do they cross?

Why does this work?

Let's use 3x + 4y = 5. If x = -1, that makes 3, the first consecutive number, negative. Then the next consecutive number, 4, is multiplied by y, which is positive 2. So 4 is added to the negative 3, giving positive 1. Then 4 more are added, making 5, the last consecutive number. So all lines of this form (even 5x + 4y = 3) pass through (-1, 2).

Maybe I'll call this the Farrell Conjecture! Or is it a theorem?