## Elementary Linear Algebra 7th Edition

$24$
The area of the triangle is given by $$\pm\frac{1}{2} \left|\begin{array}{rrr}{-4} & {0} & {1} \\ {4} & {0} & {1} \\ {0} & {6} & {1}\end{array}\right|=\pm\frac{1}{2} (6)(-4-4)=24.$$