Hello, I'm studying business economic, and I have a TMA in economic for university.
The question is to draw marginal, demand and cost curves on Microsoft Excel from a given case, I know how to draw them if we have numbers or statistics, but the problem is that we don't have any coordinates to plot the curves according to them, just to explain them before the profit reach to zero profit. As I can explain the question more for you if you want

Thanks for you time :)

Welcome to the site, Hadel,

Are you saying that you've been provided in the problem's information the various curves in function (algebraic equation) form, or can derive them from the given info?

Generally, the spreadsheet-y way of plotting a function is to set up a pair of columns, one representing the x-axis values and the other containing the y-axis values. Start by creating that first column by spreading a sequence of values spanning the reasonable range for the problem at hand. Then in the second column, immediately to the right of the first, let each cell therein calculate the y-axis value for the associated x-axis value to its immediate right.

The idea is that you're creating a sequence of data points, in the form of pairs, and you then apply the spreadsheet's plotting function to those two columns. Make the pair of columns long enough to give yourself a nice smooth curve.

Example: I know my demand function is Q = 5000 - 7P (Quantity sold as a function of Price), across a relevant price interval of [0, 100].

I create one column of prices; I have it run from 0 to 100 in (say) steps of 2 (thus the column has a length of 51 cells, running 0, 2, 4,. 100).

Then I lay in a second column where each cell contains the formula "=5000 - 7 * [cell to the immediate left]".

Plot those two columns. If 50 or so data point pairs gives a rough-looking curve, I might make the columns have a length of 100, by running the first column from 0 to 100 in steps of 1 instead of 2.