After the booster club sold 40 hotdogs at a football game, it had $90 in profit. after the next game, it had sold a total of 80 hotdogs and had a total of $210 in profit. which equation models the total profit, y, based on the number of hotdogs sold, x?

We can model the equation:y = m x + b, where y is the total profit and x is the number of hotdogs sold.The system of equations is:
90 = 40 m + b210 = 80 m + bb = 90 - 40 m210 = 80 m + 90 - 40 m210 - 90 = 40 m120 = 40 mm = 120 : 40m = 3b = 90 - 40*3b = 90 - 120b = - 30 The equation is y = 3 x - 30

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