PIVOTING RULES 



PR-1. The pivot element (a) becomes its reciprocal value (1/a). 



PR-2. The other elements in the pivot column (c) become them- 

 selves divided by the pivot element (c/a) . 



PR-3. The other elements in the pivot row (b and k^ ) become 

 themselves divided by the pivot element and given the 

 opposite sign ( — b/a and — kj/a). 



PR-4. Each element in the remaining part of the matrix (d and 

 k2 becomes itself less the quantity derived by multiplying 

 the element in the same row and in the pivot column by 

 the element in the same column and in the pivot row, and 

 dividing this product by the pivot element: d — c(b/a) 

 and k^ — c(ki/a) . 



These rules may be checked by completing the solution, that is, 

 exchanging S2 and Xo, thus solving for the X's in terms of the S's. 



II. Determining Pivot Rows and Pivot Columns 



Given: the generalized coefficient matrix: 



Xi Xo Xo ... Xq ... Xn l(Po) 



s„-= 



'pq 



Sv = 



k. 



C^ 



(Initially 

 C* = 0) 



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