Question

Find the measure of each arc. For each arc, write two or more complete sentences explaining which theorem or postulate you used to find your answer. Include your equations and calculations in your final answer.

m arcRPQ

Answer 1

arc RPQ = 305°

Explanation:

• the angle at the centre is equal to the measure of the arc that subtends it.

arc RP = ∠ ROP = 125°

∠ QOS and ∠ ROP are vertically opposite angles and are congruent, so

∠ QOS = 125° and so arc SQ = 125°

RS is a straight angle , then

∠ POS = 180° - 125° = 55°

arc PS = 55° ( arc subtending the angle at centre

Then

arc RPQ = RP + PS + SQ = 125° + 55° + 125° = 305°