Solve the System by the Addition Method $$\left\{ \begin{array} { l } x + y = 7 \\x - y = 1\end{array} \right.$$

question 38

Multiple Choice

Solve the system by the addition method. If there is no solution or an infinite number of solutions, so state. Use set
notation to express the solution set.
- $$\left\{ \begin{array} { l } x + y = 7 \\x - y = 1\end{array} \right.$$

• A) \(\{ ( 3,4 ) \}\)
• B) \(\{ ( - 4,4 ) \}\)
• C) no solution; \(\varnothing\)
• D) \(\{ ( 4,3 ) \}\)

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Definitions:

Price Level

The current pricing average for every produced good and service within the economy.

Money Demand Curve

A graph showing the relationship between the interest rate and the total amount of money that consumers and businesses wish to hold at any given time.

Nominal Variable

A variable measured in terms of money that has not been adjusted for inflation, reflecting the current price level.

Real Variable

An economic measure that has been adjusted for changes in price level, enabling comparison of quantities across different times.