Question

A circle k(O) with radius 4.5 cm is given. Through point A (OA=9 cm) draw two tangents to the circle. What is the measure of the angle between the tangents?

Answer 1

60º

Explanation:

Label the radii OB and OC where AB and AC are tangents. OB and OC are 4.5 cm as they are both radii. Then we can see that OBA and OCA are both right triangles with OBA=OCA=90º. OAB=OAC=30º because the side lengths fit the criteria for a 30-60-90 triangle. OAB+OAC=60º