21. Painting You and your friend are painting the walls in your apartment. You estimate that there is 1000 square feet of space to be painted. You paint at a rate of 4 square
feet per minute and your friend paints at a rate of 3 square feet per minute. Your
friend shows up to help you paint 45 minutes after you have already started painting.
a. Write an equation that gives the total number of square feet y as a function of the
number of minutes x it takes to paint all of the walls.
b. How long will it take you and your friend to finish painting? Round your answer
to the nearest minute.