FUСΚ ТНІЅ ЅНІТ І НАТЕ ТНІЅ ЅНІТ

The graph below shows the amount of money left in the school’s desk fund, f, after d desks have been purchased. for each new desk that is purchased, by how much does the amount of money left in the school’s desk fund decrease?

Write the system of equations represented by the matrix. 0 1 2 4 -2 3 6 9 1 0 1 3

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