(6) QP = QR therefore, triangle QPR is an isosceles triangle.
Since QPR is an isosceles triangle, the base angles are equal.
angle P + angle R + 80 = 180
2x + 80 = 180
2x = 100
x = 50.
That is just the measure of the base angle.
Now take triangle TSR.
Since R = 50, due to angle sum property, we can come up with this equation:
50 + 85 + x = 180
x = 180 - 135
x = 45 <- That's the answer.
(8) Take triangle PSQ, you get angle P = 70 degrees using the angle sum property and algebra.
Now take triangle PSR and you get angle P in the triangle as (180 - 100) / 2 = 40.
Since P = 70, and P in the smaller triangle is 40, 70 - 40 would be the answer.
x = 30 degrees <- That's the answer :D
