Hello from MrBillDoesMath!
Answer:
129
Discussion:
Angle PAR = Angle PAS + Angle SAR (*)
Angle PAR = 180 (a straight line has 180 degrees)
Substituting in (*) gives
180 = Angle PAS + Angle SAR
But Angle SAR = 51 (given) =>
180 = Angle PAS + 51 => subtract 51 from both sides
Angle PAS = 180 - 81 = 129
Since PAS is a central angle, measure of the arc PS = measure angle PAS = 129
Note: I'm assuming that arc PS refers to the smaller arc, not arc PQS ( the larger arc). The problem statement is not clear on that point.
Thank you,
MrB
