we will plot the cost on the y-axis and the number of items produced on the x-axis. thus the linear equation we seek is of the form:

C = mx + b .......where m is the slope of the line and b is the y-intercept.

so we have the points (100, 10000) and (300, 22000)

thus, the slope is given by (y2 - y1)/(x2 - x1)

=> m = (22000 - 10000)/(300 - 100) = 12000/200 = 60

so now for the equation of the line, we will use the point-slope form

=> C - C1 = m(x - x1)

=> C - 10000 = 60(x - 100)

=> C = 60x - 6000 + 10000

=> C = 60x + 4000