Corresponding Angles Theorem

Author:
Mariah
Topic:
Angles
Corresponding Angles Theorem (Postulate): If a transversal intersects two parallel lines, then corresponding angles are congruent. Given: Line AB is parallel to line CD Prove: Angle CGE and angle AHE are congruent Statements: 1. AB is parallel to line CD 2. Points E, G, H, F fall all on the same line 3. The measure of angle EGF is equal to 180 degrees 4. The measure of angle CGE + the measure of angle CGF = the measure of angle EGF 5. The measure of angle CGE + the measure of angle CGF = 180 degrees 6. The measure of angle AHE + the measure of angle CGF = 180 degrees 7. The measure of angle CGE + the measure of angle CGF = the measure of angle AHE + the measure of angle CGF 8. The measure of angle CGE + the measure of angle CGF – the measure of angle CGF = the measure of angle AHE + the measure of angle CGF – the measure of angle CGF 9. Angle CGE is congruent to angle AHE Reasons: 1. Given 2. Given 3. Definition of Straight Angle 4. Angle Addition Postulate 5. Substitution Property of Equality 6. Same-Side Interior Angles Theorem 7. Substitution Property of Equality 8. Subtraction Property of Equality 9. Definition of Congruency