I have a test tomorrow at 10 am.. it's 9:30 right now. I really need help with understanding implied domain. my teacher never fully explained it, and now i'm panicing. He would like us to put it in interval notation, with teh sideways 8 looking things. PLEASE HELP!

also, how to put a quadratic function into vertex form...

i.e. f(x)= x^2+5x+6 and g(x)= x^2+3