20. Write a two-column proof:
Given: BAC = DAC, DCA = BCA
Prove: BC = CD
![20 Write a twocolumn proof Given BAC DAC DCA BCA Prove BC CD class=](https://us-static.z-dn.net/files/d79/27b73436be99e9ead79767d647e2f9bc.png)
Given:
[tex]\angle BAC\cong \angle DAC, \angle DCA\cong \angle BCA[/tex]
To prove:
[tex]\overline{BC} \cong \overline{CD}[/tex]
Solution:
The two-column proof is:
Statement Reason
1. [tex]\angle BAC\cong \angle DAC[/tex] 1. Given
2. [tex]\angle BCA\cong \angle DCA[/tex] 2. Given
3. [tex]\overline{AC} \cong \overline{AC}[/tex] 3. Common side
4. [tex]\Delta ABC\cong \Delta ADC[/tex] 4. ASA congruent postulate
5. [tex]\overline{BC} \cong \overline{CD}[/tex] 5. CPCTC
Hence proved.