This is a linear equation y = mx, where: m= slope or reading rate: x = the number of minutes y = the number of pages read.
So the equation becomes: y = 4.5.x How many minutes it will take to read 90 pages (y): 90 = 4.5.x or x = 90/4.5 and x = 20 minutes So the ordered pair will be (20,90)