Inverse of a quadratic expression in a 2x2 matrix, like (A^2 - 5A)^-1

1. A.
   $\left(-\dfrac{1}{4}\right)\begin{pmatrix}-3 & 1\\7 & -1\end{pmatrix}$
2. B.
   $\left(\dfrac{1}{4}\right)\begin{pmatrix}-3 & 1\\7 & -1\end{pmatrix}$
3. C.
   $\left(\dfrac{1}{4}\right)\begin{pmatrix}3 & 1\\7 & 1\end{pmatrix}$
4. D.
   $\left(\dfrac{1}{-4}\right)\begin{pmatrix}3 & -1\\7 & 1\end{pmatrix}$

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1. A.
   $\dfrac{1}{95}\begin{bmatrix} 7 & 3 \\ 3 & 4 \end{bmatrix}$
2. B.
   $\dfrac{1}{95}\begin{bmatrix} -7 & 3 \\ 3 & -4 \end{bmatrix}$
3. C.
   $\dfrac{1}{95}\begin{bmatrix} -7 & -3 \\ 3 & 4 \end{bmatrix}$
4. D.
   $\dfrac{1}{95}\begin{bmatrix} 4 & 3 \\ 3 & 7 \end{bmatrix}$

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