Ali has $50 to spend on used books. Hardcover books cost $7 and paperback books cost $3 each. What equation in standard form determines the number x of hardcover books and the number y of paperback books he can buy?
The equation in standard form is

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Given f(x) = 17-x^2what is the average rate of change in f(x) over the interval [1, 5]?

Aclass consists of 55% boys and 45% girls. it is observed that 25% of the class are boys and scored an a on the test, and 35% of the class are girls and scored an a on the test. if a student is chosen at random and is found to be a girl, the probability that the student scored an ais

Carlos spent 1 1/4 hours doing his math homework he spent 1/4 of his time practicing his multiplication facts how many hours to carlos been practicing his multiplication facts