Question

The cost of printing a store flyer is $450 for 1000 copies and $880 for 2000 copies. Write a linear equation modeling this data. Then, find the amount of money it would cost to print 6245 copies.

Answer 1

Think of this as a line through two points, where the x value is the number of copies and the y value is the price. Our two points would be (1000,450) and (2000,880). The equation to find the slope is \[m=\frac{y_2-y_1}{x_2-x_1}\] and once we have the slope, we can find the line through one of the points with \[y-y_1 = m(x-x_1)\] and then use that to find the y value at x = 6245.