ANSWER
By simplifying the left hand side using the Pythagorean Identity.
EXPLANATION
The given identity is

Take the left hand side and simplify to get the right hand side.

Collect LCM for the denominators.

Recall the Pythagorean Identity.

This implies that:

We substitute this to get,


The second place runner had already completed 320 meters when the winner crossed the finish line
Answer:
see below
Step-by-step explanation:
The graph extends to the left more or less horizontally, approaching the line y=3. The only choice that expresses that is the third one.