Why did you choose those particular three locations for the congruent triangle? How did you know those points would form...

Why did you choose those particular three locations for the congruent triangle? How did you know those points would form a triangle congruent to the given triangle? Which congruency postulate or theorem (SAS, ASA, SSS, etc.) did you use to create the congruent triangle? Why did you choose it? You must include a justification for the postulate or theorem you chose accompanied by any applicable work.