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Express the situation as a system of two equations in two variables. Be sure to state clearly the meaning of your x- and y-variables. Solve the system by row-reducing the corresponding augmented matrix. State your final answer in terms of the original question. A corn and soybean commodities speculator invested $18,000 yesterday with twice as much in soybean futures as in corn futures. How much did she invest in each? X = $ invested in corn futures y = $ invested in soybean futures