Sarah and Nancy each drive 600 miles. Sarah’s average speed is represented by X miles per hour. What does the denominator of the rational expression 600/x-4 mean in context of this situation?
a. The denominator represents the time required for Nancy to drive 600 miles
b. The denominator represents Nancy’s average speed if she averages 4 mph more than Sarah.
c. The denominator represents the time required for Sarah to drive 600 miles
d. The denominator represents Nancy’s average speed if she averages 4 mph less than Sarah
