Solve for x and y begin pmatrix 1 amp 1 3 amp y... - JAMB Mathematics 1994 Question

($$\left(\begin{array}{ccc}1& 13& y\end{array}\right)$$)($$\left(\begin{array}{c}x1\end{array}\right)$$) = ($$\left(\begin{array}{c}41\end{array}\right)$$) = x + 1 = 4

x = 4 - 1

= 3

3x + y =1

3(3) = y = 1

= 9 + y = 1

y = 1 - 9

= -8