It took Gustavo 10 hours to drive to a job interview. On the way home, he was able to increase his average speed by 9mph and make the return drive in only 8 hours. Find his average speed on the return drive. Step 2 of 3 : Use the table from part 1 to help write a linear equation that represents the given word problem. (Use x to represent the unknown quantity.) Do not simplify your answer.