## Thomas' Calculus 13th Edition

$x=1-3t,y=2, z=3+7t$
The parametric equation of a straight line is defined as $v=v_1i+v_2j+v_3k$, and when it passes through a point $P(x_0,y_0,z_0)$, it is given as: $x=x_0+t v_1,y=y_0+t v_2; z=z_0+t v_3$ Here, $v=\lt -3,0,7 \gt$ and $P=(1,2,3)$ . Now, the parametric equations are: $x=1+(-3)t,y=2+t(0), z=3+(7)t$ Hence, $x=1-3t,y=2, z=3+7t$