Use Inverses to Solve Matrix Equations
- $$\begin{array} { l } - 2 x + 8 y = 60 \\2 x + 8 y = 84\end{array}$$

question 89

Multiple Choice

Use Inverses to Solve Matrix Equations
- $$\begin{array} { l } - 2 x + 8 y = 60 \\2 x + 8 y = 84\end{array}$$

• A)
• \(\left[ \begin{array} { r r } - 2 & 8 \\ 2 & 8 \end{array} \right] \left[ \begin{array} { l } x \\ y \end{array} \right] = \left[ \begin{array} { l } 60 \\ 84 \end{array} \right]\)
• B)\(\left[ \begin{array} { l l } 60 & 8 \\ 84 & 2 \end{array} \right] \left[ \begin{array} { l } x \\ y \end{array} \right] = \left[ \begin{array} { l } - 2 \\ 8 \end{array} \right]\)
• C)
• \(\left[ \begin{array} { c c } - 2 & 2 \\ 8 & 8 \end{array} \right] \left[ \begin{array} { l } x \\ y \end{array} \right] = \left[ \begin{array} { l } 60 \\ 84 \end{array} \right]\)
• \(\left[ \begin{array} { c c } - 2 & 8 \\ 8 & 2 \end{array} \right] \left[ \begin{array} { l } x \\ y \end{array} \right] = \left[ \begin{array} { l } 84 \\ 60 \end{array} \right]\)
• D)
• \(\left[\begin{array}{cc}
• -2 & 8 \\
• 8 & 2
• \end{array}\right]\left[\begin{array}{l}
• x \\
• y
• \end{array}\right]=\left[\begin{array}{l}
• 84 \\
• 60
• \end{array}\right]\)

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Definitions:

Variance

A measure of the dispersion or spread of a set of data points, calculated as the average squared deviation from the mean.

Degrees of Freedom

The number of independent pieces of information in a dataset that are available for estimating a parameter or calculating a statistic.

Student t Distribution

A probability distribution that is used in hypothesis testing for small sample sizes, when the population standard deviation is unknown.

Mean

The arithmetic average of a set of numbers, calculated by adding all the numbers together and dividing by the count of the numbers.