- #1

karush

Gold Member

MHB

- 3,269

- 5

$\textsf{Write the equation for the plane through points}$

$$A(-3,8,1),\, B(5,-7,-18),\, C(-1,-5,24)$$

ok, tried to follow an example of cross product but..

$$\displaystyle\vec{AB}\times \vec{AC} =

\begin{bmatrix}

\textbf{i} & \textbf{j} & \textbf{k}\\

\, 5 &-7 &-1\\

-1 &-5 &-1

\end{bmatrix}=$$

book answer $\color{red}{ \displaystyle 8x + 3y + z = 1 }$