We just discovered that, if you spin an object around in a circular path and then let it go, it travels on a path that is tangent to the circle. Let's take a closer look at this idea.
Line l is called the tangent line to circle C. Can you remember why point C is important? Think about that, and then click on the Answer button below to check your ideas.
Point C is the center of the circle. If you draw any line segment from point C to any point on the circle, that creates a radius. Every radius of the circle is the exact same length.
What do you think point T represents. Click on the Answer button below to check your ideas.
Point T is the point of tangency. It is the one point where the tangent line l intersects the circle C.
Is there more that can be done with the tangent line? Go on to the next page to learn about one important theorem using the tangent line to a circle.
