If $A=\left[\begin{array}{ll}x & 3 \\ 2 & y\end{array}\right], B=\left[\begin{array}{cc}2 y & 1 \\ 3 & x\end{array}\right]$ and $A+2 B=\left[\begin{array}{cc}6 & 5 \\ 8 & -2\end{array}\right]$ then the value of (x, y) is: |
$(-2,2)$ $(2,-2)$ $(4,2)$ $(0,4)$ |
$(-2,2)$ |
The correct answer is Option (1) - $(-2,2)$ $A+2 B=\left[\begin{array}{cc}x+4y & 5 \\ 8 & y+2x\end{array}\right]\left[\begin{array}{cc}6 & 5 \\ 8 & -2\end{array}\right]$ $x+4y=6$ ...(1) $y+2x=-2$ ...(2) eq. (1) × 2 - eq. (2) $2x+8y-y-2x=12-2$ $7y=14⇒y=2$ from (1) $x=-2$ $(-2,2)$ |