Question 1186429
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Statement 5 in the response from the other tutor is not valid....<br><pre>
1. BC is congruent to DC                indirect proof assumption
2. AB is congruent to AD                given
3. AC is congruent to AC
4. Triangles ACB and ACD are congruent  SSS
5. Angles BAC and DAC are congruent     corresponding parts of congruent triangles</pre>
Statement 5 contradicts the given information that angles BAC and DAC are not congruent, so the assumption that BC is congruent to DC is false.<br>
Therefore, BC is not congruent to DC, and the indirect proof is complete.<br>