Solve for the variable 4a-9=7a+12

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Acollege student takes out a $7500 loan from a bank. what will the balance of the loan be after one year(assuming the student has not made any payments yet) a. if bank charges 3.8% interest each year ?

Agatorade cooler has 36 cups of water. if a serving is 3/4 of a cup how many servings are in the cooler?

The length of a lap is 15 meters. if lisa wants to swim 450 meters this week,how many laps must she swim