All you need to do to find the rate of change is you divide the hours of sleep by the number of days or divide the right number by the left like this 15/3 = 5
y = mx + b slope(m) = -2/3 use either of ur points (1,3)...x = 1 and y = 3 now we sub and find b, the y int 3 = -2/3(1) + b 3 = -2/3 + b 3 + 2/3 = b 9/3 + 2/3 = b 11/3 = b
