Find an Equation in X and Y for the Tangent $x = e ^ { t } , \mathrm { y } = \mathrm { e } ^ { - t }$

question 13

Essay

Find an equation in x and y for the tangent line to the curve $x = e ^ { t } , \mathrm { y } = \mathrm { e } ^ { - t }$ at the point $\left( \frac { 1 } { 3 } , 3 \right)$