17. A group of students on a hiking trip wants to find the distance AB...?

Question

across a pond (see the following figure). One student suggests choosing any point C, connecting it with B, and then finding point D such that ∠DCB is congruent to angle ACB and DC is congruent to AC. How and why does this help in finding the distance AB?

Answer 1

Just look at the figure.

If angle DCB is congruent to angle ACB, then

AB will be equal to DB which can be measured easily.