The furniture factory produces  chairs in one day it costs $ and  chairs cost $.

(a)

Consider cost of the chair as  and number of chairs as  are linearly related.

Find the cost as a function of the number of chairs produces.

Here  is the input variable and  is the output.

Therefore the linear equation is .

From the data the two points are  and .

The line equation passing through the points and  is .

Substitute  and  in the line equation.

The linear equation is .

Graph :

(1) Draw the coordinate plane.

(2) Draw the linear equation .

axis : Number of chairs as .

axis : Cost of the chair as .

(b)

The two points are  and .

The slope of a line passing through the points  and   is .

Substitute  and  in the slope.

Slope is .

It represents that the marginal cost production is $ per chair.

(c)

The linear equation is .

From the graph the intercept is $.

It represents that the fixed cost is $.

(a) The linear equation is  and its graph is :

(b) Slope is , it represents that the marginal cost production is $ per chair.

(c) The fixed cost is $.