. Amelio decided to give away most of his baseball cards. He gave 15 to his best friend, and then gave
half of what he had left to his brother. After that, he
gave his cousin 10 cards, and he kept the remaining
12 for himself. How many cards did he start with?

First step is to get rid of the square root. remember that a square root is the same as raising to the (1/2) power. see below: multiply exponents per exponent rules to get: remember you subtract exponents from the denominator and add exponents in the numerator so: simplify further: so a is the correct choice. if you don't understand this google exponent rules and it will you understand. look at the image results.