Solve the system by using the inverse of the coefficient matrix.
-$x+y+z=-3$
$x-y+3 z=-21$
$4 \mathrm{x}+\mathrm{y}+\mathrm{z}=-9$
A) $(-2,4,-5)$
B) $(-5,-2,4)$
C) $(-5,4,-2)$
D) No solution

Question

Quizplus · Accepted Answer

The correct answer is A because the inverse of the coefficient matrix is $\begin{bmatrix} 1 & 1 & -1 \\ -1 & 1 & 1 \\ 4 & 1 & 1 \end{bmatrix}$ and the solution is $(-2,4,-5)$.

Solve the System by Using the Inverse of the Coefficient x+y+z=−3x+y+z=-3x+y+z=−3

Solve the System by Using the Inverse of the Coefficient $x+y+z=-3$