Answer:
C) ∠P = 140°; ∠S = 40°
Explanation:
If PQRS is a parallelogram, angle Q is adjacent to angle R.
As adjacent angles of a parallelogram sum to 180°, set the sum of angle Q and angle R to 180°, and solve for x:
⇒ ∠Q + ∠R = 180°
⇒ (x + 15)° + (6x - 10)° = 180°
⇒ x + 15 + 6x - 10 = 180
⇒ 7x + 5 = 180
⇒ 7x = 175
⇒ x = 25
Substitute the found value of x into the expressions for angle Q and angle R:
⇒ ∠Q = (x + 15)°
⇒ ∠Q = (25 + 15)°
⇒ ∠Q = 40°
⇒ ∠R = (6x - 10)°
⇒ ∠R = (6(25) - 10)°
⇒ ∠R = (150 - 10)°
⇒ ∠R = 140°
The opposite angles of a parallelogram are equal.
Angle P is opposite angle R, so ∠P = 140°.
Angle Q is opposite angle S, so ∠S = 40°.