Answer:
(a) y = 25°
(b) x = 90°
(c) z = 25°
Step by step explanation:
Part A
z + 90° + 65° = 180°
z = 180° - 65° - 90°
z = 25°
Part B
x + 90° = 180°
x = 90°
Part C
x + 65° + y = 180°
90° + 65° + y = 180°
y = 25°
A straight line has total 180° angle. A square has 4 sides of each 90° angle. A triangle is build up of 180° interior angle.