Christy drove at an average speed of 55 mi/h from her home in San Francisco to visit her sister in Tucson. She stayed in Tucson 10 hours, and on the trip back averaged 35 mi/h. She returned home 50 hours after leaving. How many miles is San Francisco from Tucson? a) Write an equation using the information as it is given above that can be solved to answer this question. Use t as your variable to represent the amount of time Christy spent driving from San Francisco to Tucson. Equation:

(d / 55) + (d / 35) = 50 - 10

To solve this question, we can use the equation:

Distance = Speed * Time

Let's denote the distance between San Francisco and Tucson as "d", and the time it takes Christy to drive from San Francisco to Tucson as "t".

From the given information, we know that Christy drove at an average speed of 55 mi/h from her home in San Francisco to Tucson. Therefore, the distance Christy traveled from San Francisco to Tucson can be expressed as:

Distance from San Francisco to Tucson = Speed * Time
d = 55t (Equation 1)

We also know that Christy stayed in Tucson for 10 hours. Therefore, the time it took for the return trip from Tucson to San Francisco is equal to the time spent driving from San Francisco to Tucson plus the time she stayed in Tucson.

Return trip time = Time from San Francisco to Tucson + Time spent in Tucson
50 = t + 10 (Equation 2)

We now have a system of two equations:

Equation 1: d = 55t
Equation 2: 50 = t + 10

We can solve this system of equations simultaneously to find the values of "d" and "t".