Find Which of the Following Matrices Is an Inverse to the Matrix

question 88

Multiple Choice

Find which of the following matrices is an inverse to the matrix A below if any. $A = \left[ \begin{array} { c c } - 4 & - 3 \\- 1 & 7\end{array} \right]$ Matrix I: $\frac { 1 } { 31 } \left[ \begin{array} { c c } - 7 & - 3 \\ - 1 & 4 \end{array} \right]$
Matrix II : $\frac { 1 } { 31 } \left[ \begin{array} { c c } 4 & 3 \\ 1 & - 7 \end{array} \right]$
Matrix III : $\frac { 1 } { 31 } \left[ \begin{array} { c c } 7 & - 3 \\ - 1 & - 4 \end{array} \right]$

• A)Each of the matrices I and II is an inverse of A.
• B)Each of the matrices I and III is an inverse of A.
• C)Matrix II is an inverse of A.
• D)Matrix I is an inverse of A.
• E)None of the matrices is an inverse of A.

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Definitions:

Annual Interest Rate

The percentage of interest that is charged or earned on an investment or loan over the course of a year.

Revolving Line

A credit arrangement that allows a borrower to use or withdraw funds up to a designated limit, repay them, and borrow again.

Simple Interest

A method of calculating interest where the interest charge is based only on the original principal, not on the interest which has been added over time.

Annual Rate

The interest rate for a period of one year.