Discover Questions

Why does sqrt(4)-sqrt(16) not equal two? If sqrt(4) equals +-2 and sqrt(16) equals +-4, then could you not say -2+4 = 2? How to divide large decimals without a calculator? 679.788 divided by 130.968 Steps would be greatly appreciated
Thanks in advance? Tell me an antidepressant pill that actually works. Or a list of pills giving relative benefit.? Is Earth the oldest planet in the Milky Way galaxy? A kid moving 3.18 m/s jumps on a slip and slide (Uk=0.0751). How far has he slid when his velocity is reduced to 2.00 m/s?
Please help!!?