The equation of the common "heart"

So I was bored today, despite me supposed to be studying, I always wondered if the "heart shape" had an equation.. Guess what? After 5 seconds of googling, and more seconds spent fiddling with available graph drawing software I have, I created myself a heart :*)

This is the link I'm talking about. There are plenty.. The two that interest me most are the standard x-y and polar equation. :*)



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