Question 68325
Without changing the inclination of your neck and head, turn sideways until the visor is in line with a point on your side of the stream.
- Measure the distance BD between your feet and that point.
QUESTIONS
a.) From the description of the measuring method, what corresponding parts of the 2 triangles can you assume are congruent? 
The angle your body makes with the ground is a rt. angle; The angle made
by your body and the line to the opposite shore and/or the distant object
The side from your feet to the opposite shore and/or the side from your
feet to the distant object. The side formed by your body in both triangles.
b.) What theorem or postulate can be used to show that the 2 triangles are congruent? Side-Angle-Side

c.) Explain why the length of BD is also the distance across the stream.
Corresponding parts of congruent triangles.
Cheers,
Stan H.