Formulate the the situation as a system of linear equations. Solve using the Gauss-Jordan method.

A large commercial farm needs 43,500 pounds of potash, 83,500 pounds of nitrogen, and 31,000 pounds of phosphoric acid. Three brands of fertilizer, Growrite, MiricalMix and GreatGreen, are available and contain the amounts of potash, nitrogen and phosphoric acid per truck load listed in the table. How many truckloads of each brand should be used to provide the required potash, nitrogen and phosphoric acid?

X1=______ truckloads of GrowRite

X2= _____  truckloads of MiracleMix

X3= _____  truckloads of GreatGreen

                                       GrowRIte           MiracleMix        GreatGreen

Potash                               400                     600                 700

Nitrogen                             500                     1000               1600

Phosphoric Acid                   300                      400                  500