Which of the following is the standard form of the polynomial function y = x(x + 5)(x − 3)? y = x2 + 2x − 15
y = x3 − 8x2 − 15x
y = x2 − 8x − 15
y = x3 + 2x2 − 15x

Sam opened a money-market account that pays 3% simple interest. he started the account with $7,000 and made no further deposits. when he closed the account, he had earned $420 in interest. how long did he keep his account open?

The product of 3 and a number increased by 8 is 31

Last month, leonhard euler's watch kiosk at the mall had total sales of $9,489. merchandise totaling $225 was returned. the goods that were sold cost leonhard euler's $5,481. operating expenses for the moth were $992. what was the gross profit on sales?