The cost of producing 6000 face masks is $25,600, and the cost of producing 6500 face masks is $25,775. We can use this information to find the slope of the line that represents the cost of producing face masks. The slope is the change in cost divided by the change in the number of face masks produced:
slope = (25775 - 25600) / (6500 - 6000) = 3.5
The vertical intercept for this graph is at the point (0, 200) and represents a cost of $200 when a quantity of 0 face masks are produced. The rate of change for C(a) is 3.5 and means the cost is increasing by $3.50 for every additional thousand face masks produced.
The linear equation for C(x) is C(x) = 3.5x + 200.
Based on this model, C(11) = 3.5(11) + 200 = 238.5, which means that when a quantity of 11,000 face masks are produced, there is a cost of $238.50.
Solving C(x) = 90,700 shows x = 25.5, which represents that for a cost of $90,700, you can produce 25,500 face masks.
The appropriate domain of this function is (0, INF) (interval notation- use INF for infinity if needed).