Unit G Summary Question #6: Holes

6. How do we find the appropriate place to plot a hole if the y-value is undefined when plugged into the original equation?

Normally, when we want to find the value of the function we plug in the x value into the original equation and we get a y-value to plot the (x,y) point. However, with holes, we must remember that it is when any common factors cancel out. Therefore, we have a new simplified equation. If we plug in the x value into the original equation, the y-value is undefined. We have to evaluate by using the simplified equation to get the real y-value of the hole. Then, while it is not an actual "real" point of the graph we use an open circle to graph the hole.