If $\begin{bmatrix}2x & -7\\5y & 8\end{bmatrix}=\begin{bmatrix}6 & -7\\-5 & 3x+y\end{bmatrix}$ then value of $(5x+3y)$ is :
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 12
$\begin{bmatrix}2x & -7\\5y & 8\end{bmatrix}=\begin{bmatrix}6 & -7\\-5 & 3x+y\end{bmatrix}$
$2x=6;x=3$
$5y=-5;y=-1$
$∴5x+3y=5(3)+3(-1)=12$