Let x, represent the number of minutes and y represents the number of gallons of water in the tub, then the ordered pairs (2, 30) and (5, 12) satisfies the equation.
Therefore the equation is given by: (y - 30)/(x - 2) = (12 - 30)/(5 - 2) (y - 30)/(x - 2) = -18/3 x = -6 y - 30 = -6(x - 2) = -6x + 12 y = -6x + 42
First you would multiply $59.92 and 0.07 together and get 4.1944. Round this and get 4.19. Then you would subtract this from the total price to get 55.73.
