Two supporting reasons are missing from the proof. complete the proof by dragging and dropping the appropriate reasons into each of the empty boxes. given: m∥n m∠3=120°prove: m∠8=60°  statements           reasons m∥nm∠3=120° given∠5≅∠3 m∠5=m∠3 angle congruence postulatem∠5=120° substitution property of equalitym∠8+m∠5=180° linear pair postulatem∠8+120°=180° m∠8=60° subtraction property of equality  answer choices:   1. angle addition postulate2. alternate interior angles theorem3. substitution property of equality4. alternate exterior angles theorem

The answer is alternate interior angles theorem and substitution property of equality.

step-by-step explanation:

you divide the denominator by the numerator on both sides and if the quotients are equal then the fractions are equivalent

proofs involving isosceles triangles often require special consideration because an isosceles triangle has several distinct properties that do not apply to normal triangles.(more about triangle types) therefore, when you are trying to prove that two triangles are congruent, and one or both triangles, are isosceles you have a few theorems that you can use to make your life easier.

step-by-step explanation:

an isosceles triangle has two congruent sides and two congruent angles. the congruent angles are called the base angles and the other angle is known as the vertex angle. ∠bac and ∠bca are the base angles of the triangle picture on the left. the vertex angle is ∠abc