Lesson 7-2: Angle Relationships and Triangles — Practice Questions

1. 1. In a triangle, two interior angles measure $35°$ and $75°$. The exterior angle adjacent to the third interior angle measures ___°.

2. 2. An exterior angle of a triangle measures $135°$. One of the two remote interior angles measures $72°$. What is the measure of the other remote interior angle?

   • A. 53°
   • B. 63°
   • C. 45°
   • D. 72°

3. 3. An interior angle of a triangle measures $48°$. What is the measure of its adjacent exterior angle?

   • A. 48°
   • B. 132°
   • C. 142°
   • D. 52°

4. 4. In triangle $ABC$, $m\angle A = 55°$ and $m\angle B = 45°$. The exterior angle at vertex $C$ measures ___°.

5. 5. Which statement correctly describes the Exterior Angle Theorem?

   • A. An exterior angle equals the difference of the two remote interior angles.
   • B. An exterior angle equals the sum of the two remote interior angles.
   • C. An exterior angle is always greater than $180°$.
   • D. An exterior angle equals the adjacent interior angle.

6. 6. Two angles in a triangle measure $45^\circ$ and $65^\circ$. What is the measure of the third angle in degrees? ___

7. 7. A right triangle has one angle that measures $22^\circ$. What is the measure of the third angle?

   • A. $22^\circ$
   • B. $68^\circ$
   • C. $90^\circ$
   • D. $158^\circ$

8. 8. An isosceles triangle has a unique angle of $80^\circ$. The other two angles are equal. What is the measure of one of the equal angles in degrees? ___

9. 9. An isosceles triangle has two equal base angles that each measure $55^\circ$. What is the measure of the third, unique angle?

   • A. $55^\circ$
   • B. $125^\circ$
   • C. $70^\circ$
   • D. $110^\circ$

10. 10. Which set of angles could form a valid triangle?

    • A. $60^\circ, 60^\circ, 70^\circ$
    • B. $90^\circ, 45^\circ, 45^\circ$
    • C. $100^\circ, 40^\circ, 50^\circ$
    • D. $30^\circ, 60^\circ, 80^\circ$