Question

What is the value of p ?

Answer 1

For any triangle, the sum of the interior angles is 180°. Additionally, the sum of two supplementary angles in 180°

Thus:

p=180-(180-90)-(180-125)
p=180-(90)-(55)
p=35°

Answer 2

Angle next to the 90° = 90° (because of straight line angle)
Angle next to 125° = 55° (again because of straight line angle)

A triangle = 180°

180 = 90 + 55 + p

Simplify

180 = 145 + p

Isolate the p, subtract 155 from both sides

180 (-145) = 145 (-145) + p

p = 180 - 145
p = 35

C) 35° is your answer


hope this helps