According to Google Maps, the distance from Phoenix to Anaheim is approximately 375 miles.
Now, let's assume the vehicle being used gets 25 miles per gallon (mpg) of gas.
To calculate the number of gallons of gas required, we can use the following formula:
Number of gallons = Distance (in miles) / Fuel efficiency (in mpg)
Plugging in the values we have:
Number of gallons = 375 miles / 25 mpg
= 15 gallons
Therefore, it will take approximately 15 gallons of gas to get from Phoenix to Anaheim.