Chapter 4 Quadratic Functions and Factoring - 4.2 Graph Quadratic Functions in Vertex or Intercept Form - 4.2 Exercises - Mixed Review - Page 251: 66

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Given: $B+C=\begin{bmatrix} 2 & -6\\ 3 & -8 \end{bmatrix}+\begin{bmatrix} -1& 4\\ -2 & 3 \end{bmatrix}=\begin{bmatrix} 1& -2\\ 1 & 11 \end{bmatrix}$ Hence, $3\begin{bmatrix} 1 & -2\\ 1 & 11\end{bmatrix}=\begin{bmatrix} 3.1 & 3.(-2)\\ 3.1 & 3.11 \end{bmatrix}=\begin{bmatrix} 3& -6\\ 3 & 33 \end{bmatrix}$