I need help solving this problem

The graph shows the rate at which paint is used to paint a wall. enter values to complete each statement below based on the graph. when 1 gallon of paint has been used, ( # ) square feet of the wall will be painted. the unit rate is ( # )square feet per gallon.

Ineed with number 6 , explain how to get 1978

How can writing phrases as algebraic expressions you solve problems?