Answer:
mPS = 80°
Step-by-step explanation:
angles on a circle subtended by the same arc are congruent
∠ PQS and ∠ PRS are both subtended by arc PS , then
10 + 3x = 110 - 7x ( add 7x to both sides )
10 + 10x = 110 ( subtract 10 from both sides )
10x = 100 ( divide both sides by 10 )
x = 10
then
∠ PQS = 110 - 7x = 110 - 7(10) = 110 - 70 = 40°
the inscribed angle PQS is half the measure of its intercepted arc PS , then
PS = 2 × 40° = 80°
