Here's the question you clicked on:
AriPotta
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you may not know this, but we have this equation of trajectory of a particle in physics. its a quadratic equation.
ok imagine, you threw a ball at an angle upwards. |dw:1362421342726:dw| like this. this is a parabola, which means a quadratic equation.
you could say trajectory of a particle when thrown upwards at an angle.
http://openstudy.com/study#/updates/4e9303310b8bfb9f23eff5b1 take a look. i googled your question. :P
haha. sadly this was the last one. :c