SOLUTION: what is the proof for the collary to theorem 4.7 (converse of the base angles theorem?)

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Question 564532: what is the proof for the collary to theorem 4.7 (converse of the base angles theorem?)
Answer by Edwin McCravy(20060)   (Show Source): You can put this solution on YOUR website!
Given: ᐃABC 
∠A ≅ ∠B
To Prove: AC ≅ BC



Draw altitude CD ⊥ AB

1. m∠ADC = m∠BDC = 90°            1.               
2. ∠ADC and ∠BCD are              2.
   (congruent) right angles 
3. ∠A, ∠ACD are complementary     3. 
4. ∠B, ∠BCD are complementary     4.
5. ∠ACD ≅ ∠BCD                    5.
6. CD ≅ CD                        6.
7. ᐃACD ≅ ᐃBCD                    7. ASA, steps 1,6,5
8. AC ≅ BC                        8.  

Be sure to fill in the reasons.
Edwin
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