I received a pre-alg worksheet in class a while back, but have forgotten/never learned two of the problem methods. They are both because i forgot what the symbol means...

I don't know how to write these questions, so i scanned them. i don't understand what the 3 means on the right one, and i think i got the left one right... that check-mark symbol just means to find the square root, right?

And this one. What does the / part mean?

Thanks in advance.