Problem 278
Write the line through M_1(3,-2,-4) parallel to 3x-2y-3z-7=0…
Write the line through $M_1(3,-2,-4)$ parallel to $3x-2y-3z-7=0$ and intersecting $\tfrac{x-2}3=\tfrac{y+4}{-2}=\tfrac{z-1}2$.
Explanation of Method
The line through M₁ that is parallel to a plane and meets a given line.
Step 1: Solution
Take $A=(2+3t,-4-2t,1+2t)$. Then $\overrightarrow{M_1A}=\{3t-1,-2-2t,5+2t\}$, and $\overrightarrow{M_1A}\cdot\{3,-2,-3\}=7t-14=0$ gives $t=2$, so $A(8,-8,5)$.
\[\frac{x-3}{5}=\frac{y+2}{-6}=\frac{z+4}{9}\]
Check: $15+12-27=0$, and $M_1$ is not in the plane ($18\ne0$).
$M_1$
$A(8,-8,5)$
$\ell$
Result
\[\boxed{\,\frac{x-3}{5}=\frac{y+2}{-6}=\frac{z+4}{9}\,}\]