Given: Angle1 and Angle2 are complements, Angle2 and Angle3 are complements, and mAngle1 = 35°. Prove: mAngle3 = 35° 4 lines extend from a point and form 3 angles. The angles are labeled 1, 2, 3 from left to right. Complete the missing parts of the paragraph proof. By the , we know that angle 1 is congruent to angle 3. The measure of angle 1 equals the measure of angle 3 by the definition of ___ angles. Then, using the property, the measure of angle 3 is degrees.