Paul is comparing the cost of cell phone services. at cellcoa, the phone he wants costs $305 and the unlimited calling plan costs $45 per month. at cellcob, paul can purchase the same phone for $350 and get an unlimited calling plan for $30 per month. in how many months will both plans cost the same? these equations, which are graphed below, represent the situation. y = 45x + 305 y = 30x + 350 here, x represents the number of months and y represents the amount paid.

In 3 months the cost will be the same, they will both cost $440, A is expressed as Cost = 305 + 45m (months) while B is expressed as Cost = 350 +30m because their cost will be the same equation A will equal equation B, 305 +45m = 350 +30m, subtract 30m from both sides to get 305+15m = 350, then subtract 305 from both sides to get 15m = 45, divide by 15 to get m to get m=3 which equals to x=3 input x in both equations to get your y, y = 45(3) + 305 and y= 30(3) + 350, they both give you the answer y= 440 so the point they intersect at is (3,440)