1. **Problem 1: Complementary Angles** A right angle measures 90°. Two angles are complementary if their sum is 90°. Given: $x = 40^\circ$ Find: $y$ Formula: $x + y = 90^\circ$ Calculation: $$y = 90^\circ - x = 90^\circ - 40^\circ = 50^\circ$$ So, $y = 50^\circ$. 2. **Problem 2: Supplementary Angles** Two angles are supplementary if their sum is 180° (a straight line). Given: $A = 120^\circ$ Find: $B$ Formula: $A + B = 180^\circ$ Calculation: $$B = 180^\circ - A = 180^\circ - 120^\circ = 60^\circ$$ So, $B = 60^\circ$. 3. **Problem 3: Vertically Opposite Angles** When two lines intersect, opposite angles are equal. Given: $\angle 1 = 70^\circ$ Find: Vertically opposite angles to $\angle 1$ Rule: Vertically opposite angles are equal. Therefore, the vertically opposite angle to $\angle 1$ is also $70^\circ$. 4. **Problem 4: Full Turn Angles** A full turn around a point is a complete circle. Rule: A full turn measures $360^\circ$. Answer: The angle of a full turn is $360^\circ$. **Summary of answers:** - $y = 50^\circ$ - $B = 60^\circ$ - Vertically opposite angles to $\angle 1$ are $70^\circ$ - Full turn angle is $360^\circ$.