How long does it take to pay off your 30 year Mortgage?

i'm actually a fan of leverage...if you can lock in long term fixed debt right now, i don't understand paying cash from an investment perspective--put emotions and ideas of your comfort zone away and just look at the math...by paying off a mortgage early, you're effectively earning the interest rate of that mortgage on your cash...so around 6%...if you're a half decent investor, you should be able to better than that, and stay leveraged.....and btw, that was a terrible post...your profile says you're a student..maybe it's bc i don't trust a lot of people, but what's your angle??