Use the Inverse Formula $A ^ { - 1 } = \frac { 1 } { a d - b c } \left[ \begin{array} { c c } d & - b \\- c & a\end{array} \right]$

question 97

Multiple Choice

Use the inverse formula $A ^ { - 1 } = \frac { 1 } { a d - b c } \left[ \begin{array} { c c } d & - b \\- c & a\end{array} \right]$ to find the inverse of the matrix (if it exists) .
$\left[ \begin{array} { c c } - 7 & - 9 \\7 & 9\end{array} \right]$

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Real GDP

Gross Domestic Product corrected for inflation levels, offering a clearer view of the economy's scale and its growth trajectory over time.

Billion

A numerical value representing one thousand million (1,000,000,000) in the short scale, and commonly used in financial contexts.

Year

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Trade Surplus

A situation in which a country's exports exceed its imports, leading to a positive balance of trade.