## The Multiplication Parabola

In the graph below, move points and such that they are on opposite sides of the *y*-axis. What do you observe?

[iframe http://mathandmultimedia.com/wp-content/geogebraapplets/multiplicationinparabola/parabolamultiplication.html 500 400]

**Theorem:** Given two points on the function , whose coordinates are and with and , the *y*-intercept of the line passing through these points is . » Read more