Question

Help solve this matrix problem for -4a+2b=

Answer 1

Step-by-step explanation:

$A = \begin{bmatrix} - 3 & 1\\ - 6 & 9\end{bmatrix} \: and \: B = \begin{bmatrix} - 4 & - 3 \\ - 9 & 9\end{bmatrix} \\\\-4A+2B = - 4\begin{bmatrix} - 3 & 1\\ - 6 & 9\end{bmatrix} + 2\begin{bmatrix} - 4 & - 3 \\ - 9 & 9\end{bmatrix} \\\\-4A+2B = \begin{bmatrix} - 3(-4) & 1(-4)\\ - 6(-4)& 9(-4)\end{bmatrix} + \begin{bmatrix} - 4(2) & - 3(2) \\ - 9(2) & 9(2)\end{bmatrix} \\\\-4A+2B = \begin{bmatrix}12 & -4\\ 24& -36\end{bmatrix} + \begin{bmatrix} - 8 & - 6 \\ - 18 & 18 \end{bmatrix} \\\\-4A+2B = \begin{bmatrix}12+(-8) & -4+(-6)\\ 24+(-18)& -36+18\end{bmatrix} \\\\-4A+2B = \begin{bmatrix}12-8 & -4-6\\ 24-18 & -36+18\end{bmatrix} \\\\\huge\red{-4A+2B }= \orange {\begin{bmatrix}4 & -10\\ 6 & -18\end{bmatrix}}$