Check out the XL help for the LINEST function. It contains an example of a
multi-variate regression very much like what you want.

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Regards,

Tushar Mehta
www.tushar-mehta.com
Excel, PowerPoint, and VBA add-ins, tutorials
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In article ,
says...
I have to make a model Y=a*X1+b*X2+c with Solver when a, b and c are the
tuning parameters. And then make a figure which shows the values of Y and
the model values.

I have this data set, which have the values to Y, X1 and X2

Y X1 X2
2,3 0 5,98
2,167 1,76 0,64
2,484 0,82 6,16
2,804 2,99 2,56
2,682 0,3 4,19
0,311 0,12 0,3
0,147 0,11 0,14
1,396 1,58 1,8
0,516 0,6 0,41
0,679 0,35 0,23
1,038 1,45 0,76
1,323 1,95 0,67
1,491 1,77 1
2,524 2,32 2,93
1,906 2,34 0,54
0,187 0,3 0,21
0,401 0,53 0,22
0,185 0,28 0,27
0,234 0,25 0,16
0,368 0,36 0,26

Anyone who could help me whit this?