The diagram below depicts a right triangle with an altitude, $\displaystyle {l}$, drawn from the vertex of its right angle to its hypotenuse. Use the acute angle $\displaystyle \angle{K}$ as a reference angle to find three distinct expressions for $\displaystyle {\cos{{\left({K}\right)}}}$. Separate each expression with a comma and one space exactly in the box below. 

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 $\displaystyle {\cos{{\left({K}\right)}}}=$