Geometry Number of players: 2 Materials: Spinners

One Thing Leads to Another

You know that certain pairs of angles are congruent when a pair of parallel lines is intersected by a transversal. Parallel lines intersected by a transversal have another interesting property: The interior angles on the same side of the transversal are supplementary. In other words, the interior angles on the same side of the transversal have a combined measure of 180°.

Label equal sections of one spinner with the letters A through H. Label equal sections of a second spinner with the following angle measures: 84°, 120°, 60°, 30°, 110°, 45°.

Each partner spins a spinner. Try to be the first to write the measure of all of the other angles in a figure like the one shown on the back of this card if the angle shown on the first spinner has the angle measure shown on the second spinner. (Note: The figure shows the locations of angles A through H only. The actual measures of angles A through H depend on the results of your spins.)