Solve the System by the Addition Method, If Possible $$\left\{ \begin{array} { c } 2 ( x + y ) = y - 19 \\7 ( x + 10 ) = y + 17\end{array} \right.$$

question 7

Multiple Choice

Solve the system by the addition method, if possible. If a solution exists, give the value of x. $$\left\{ \begin{array} { c } 2 ( x + y ) = y - 19 \\7 ( x + 10 ) = y + 17\end{array} \right.$$

• A) \(- 5\)
• B) \(- 11\)
• C) \(- 2\)
• D) \(- 8\)
• E) no solution

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Definitions:

Variable Costs

Costs that change in proportion to the level of goods or services that a business produces.

Profit-maximizing Output

The level of production at which a firm achieves the highest profit, where marginal revenue equals marginal cost.

Marginal Cost

The expenditure required to produce an extra unit of a good or service.

Fixed Cost

A cost that does not change with an increase or decrease in the amount of goods or services produced.