Solve the System by Using the Inverse of the Coefficient $$\begin{array} { l } - 3 x + y + 3 z - w = - 1 \\- x - 4 y + z - 2 w = - 15 \\- 4 x + 3 y - 3 z + w = 20 \\3 x - y - z - 2 w = - 6\end{array}$$

question 426

Multiple Choice

Solve the system by using the inverse of the coefficient matrix.
- $$\begin{array} { l } - 3 x + y + 3 z - w = - 1 \\- x - 4 y + z - 2 w = - 15 \\- 4 x + 3 y - 3 z + w = 20 \\3 x - y - z - 2 w = - 6\end{array}$$

• A) \(\{ ( - 1 , - 3,2 , - 1 ) \}\)
• B) \(\{ ( - 3,4 , - 1 , - 1 ) \}\)
• C) \(\varnothing\)
• D) \(\{ ( - 1,3 , - 2,1 ) \}\)

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Promotion-to-Sales Ratio

A metric comparing the amount spent on marketing and promotion to the total sales revenue generated, often used to assess marketing efficiency.

Total Promotion Expenditures

The aggregate amount of money a company spends on all promotional activities, including advertising, sales promotions, public relations, and personal selling, over a set period.

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Expenses related to promoting and selling a product or service, including advertising, market research, and distribution.

Unit Sales Price

The cost at which individual units of a product are sold to consumers or retailers.