Note: I solved them as follows:
$x = 3, -2$ but the textbook i'm using said there was no solution for $x$
$x=-2, 9$ but the same textbook simply said $x=9$
- I wasn't able to do the third one (i reached a dead end where i had to take the root of a negative number)
Please, can anyone help me simplify the three equations in detail, and if possible, tell me where i might have made a mistake?