Answer:
A. 45°
Explanation:
m<PSR is given as 99° = m<PSQ + m<QSR
m<PSQ = (3x + 18)°
m<QSR = (9x - 27)°
99 = (3x + 18) + (9x - 27)
Find the value of x using the expression above
99 = 3x + 18 + 9x - 27
99 = 12x - 9
Add 9 to both sides
99 + 9 = 12x
108 = 12x
Divide both sides by 12
9 = x
x = 9
Find m<PSQ
m<PSQ = (3x + 18)°
Plug in the value of x
m<PSQ = 3(9) + 18
m<PSQ = 27 + 18 = 45°