4x + 5y = 12 and 3x + 4y = 9.25 . Solve for systems of equations

7(x - 2) = 3(x + 4) solve the following equation. then enter your answer in the space provided using mixed number format.

For the rule of 78, for a 12-month period, the last term in the sequence is 12 and the series sums to 78. for an 10 month period, the last term is and the series sum is . for a 15 month period, the last term is and the series sum is . for a 20 month period, the last term is and the series sum is

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