WAEC - Further Mathematics (2006 - No. 29)
Given that \(\begin{pmatrix} 1 & -3 \\ 1 & 4 \end{pmatrix} \begin{pmatrix} -6 \\ P \end{pmatrix} = \begin{pmatrix} 3 \\ -26 \end{pmatrix}\), find the value of P.
-8
-5
4
-3
Εξήγηση
\(\begin{pmatrix} 1 & -3 \\ 1 & 4 \end{pmatrix} \begin{pmatrix} -6 \\ P \end{pmatrix} = \begin{pmatrix} 3 \\ -26 \end{pmatrix}\)
\(\implies (1 \times -6) + (-3 \times P) = 3\)
\(-6 - 3P = 3 \implies -3P = 9\)
\(P = -3\)