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Eliminate the parameter. x = 5 cos t, y = 5 sin t help please!

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\bf \begin{cases} x=5cos(t)\implies \cfrac{x}{5}=cos(t)\\\\ y=5sin(t)\implies \cfrac{y}{5}=sin(t) \end{cases} \\\\\\ \textit{now, recall that }sin^2(\theta)+cos^2(\theta)=1\qquad thus \\\\\\ \left( \cfrac{x}{5} \right)^2+\left( \cfrac{y}{5} \right)^2=1\implies \cfrac{x^2}{5^2}+\cfrac{y^2}{5^2}=1\implies \cfrac{x^2+y^2}{25}=1 \\\\\\ x^2+y^2=25\implies x^2+y^2=5^2\impliedby \textit{which is just a circle}
User Anders Kaseorg
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