-6x+6y=42
help me big test question

At the beginning of the day, stock xyz opened at $6.12. at the end of the day, it closed at $6.88. what is the rate of change of stock xyz? a. 1.17% b. 11.0% c. 12.4% d. 81.5%

This is so hard and it’s for a test

How far could you drive on 50 gallons of gas