This demo shows the linear function in one variable L(x) = px +k over the domain 0 ≤ x ≤ 1. You can change the constants p and k using the respective red or purple slide bar, and the Graph: L(x,y) window will show the function graph of L(x,y) with the chosen values for the constants.

If you slide the hotspot on the purple slidebar, (thereby varying the constant k) the function graph is translated up and down. Varying the hotspot on the red slidebar (thereby varying the slope p) will change the slope of the function.