Can someone explain how to answer #18?

Which graph represents the linear function below? y-4= (4/3)(x-2)

Pranav and molly are selling pies for a school fundraiser. customers can buy blueberry pies and pumpkin pies. pranav sold 6 blueberry pies and 4 pumpkin pies for a total of $106. molly sold 6 blueberry pies and 3 pumpkin pies for a total of $90. find the cost of each of one blueberry pie and one pumpkin pie

Me because i don't understand how to do it.: )