For matrix $A=\begin{bmatrix} 3 & 1\\7 & 5\end{bmatrix},$ the values of x and y so that $A^2+xI=yA$ are :
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → $x=8, y = 8$
$A^2+xI=yA$
and,
$A=\begin{bmatrix}3&1\\7&5\end{bmatrix}$
$∴A^2+xI=\begin{bmatrix}16+x&8\\56&32+x\end{bmatrix}=y\begin{bmatrix}3&1\\7&5\end{bmatrix}$
$⇒(x,y)=(8,8)$