Problem
Given the matrices \( A \) and \( B \) shown below, find \( -A-4 B \). \[ A=\left[\begin{array}{cc} -2 & 0 \\ 3 & -5 \\ 0 & 4 \\ 2 & 5 \end{array}\right] \quad B=\left[\begin{array}{cc} -6 & 4 \\ -2 & 4 \\ 1 & 5 \\ 3 & 2 \end{array}\right] \] Rows: \( 2 \odot \odot \) Columns: \( 2 \odot \oplus \) Submit Answer
Solution
Step 1 ：(-1)A = \left[\begin{array}{cc} 2 & 0 \\ -3 & 5 \\ 0 & -4 \\ -2 & -5 \end{array}\right]
Step 2 ：(-4)B = \left[\begin{array}{cc} 24 & -16 \\ 8 & -16 \\ -4 & -20 \\ -12 & -8 \end{array}\right]
Step 3 ：(-A-4B) = \left[\begin{array}{cc} 2+24 & 0-16 \\ -3+8 & 5-16 \\ 0-4 & -4-20 \\ -2-12 & -5-8 \end{array}\right] = \left[\begin{array}{cc} 26 & -16 \\ 5 & -11 \\ -4 & -24 \\ -14 & -13 \end{array}\right]
