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kgibbs1219
May 18, 2008, 04:38 PM
If a company manufactures 20 widgets it cost $405, the cost of manufacturing 500 is $1125. Assume the cost C depends linearly on the number x of widgets manufactured.

express the cost n terms of the number of widgets manufactured

Capuchin
May 18, 2008, 04:47 PM
You have 2 points on the graph, so you can just take the generic equation for a line:

y = mx + c

and work out what m and c must be.

What specifically are you having trouble with?

kgibbs1219
May 18, 2008, 04:50 PM
Which numbers do I plug where?

Capuchin
May 18, 2008, 04:58 PM
m is the gradient of the line, i.e.

m = \frac{\Delta y}{\Delta x} = \frac{y_2 - y_1}{x_2 - x_1}

and c can be obtained by plugging in one of the points.
This can then be verified with the other point.

kgibbs1219
May 18, 2008, 05:15 PM
I got! Thank you