In the figure below, angle y and angle x form vertical angles. Angle y forms a straight line with the 80° angle and the 60° angle. A straight line is shown and is marked with three angles. The first angle measures 80 degrees. The second angle measures 60 degrees. The third angle is labeled y. The line between the 60 degree angle and angle y extends below the straight line. The angle formed is labeled angle x. Write and solve an equation to determine the measure of angle x.