An Augmented Matrix That Represents a System of Linear Equations $x$

question 87

Multiple Choice

An augmented matrix that represents a system of linear equations (in variables $x$ , $y$ , and $z$ ) has been reduced using Gauss-Jordan elimination. Write the solution represented by the augmented matrix.
$$\left[ \begin{array} { c c c : c } 1 & 0 & 0 & 9 \\0 & 1 & 0 & 8 \\0 & 0 & 1 & - 7\end{array} \right]$$

• A) \(x = 9 , y = 8 , z = - 7\)
• B) \(x = - 9 , y = - 8 , z = 7\)
• C) \(x = 0 , y = 0 , z = 0\)
• D) \(x = 9 x , y = - 7 y , z = 8 z\)
• E) \(x = 9 , y = 0 , z = 0\)

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Definitions:

Relevant Range

The range of activity within which assumptions about variable and fixed cost behaviors are valid.

Gross Margin

A company's net sales revenue minus its cost of goods sold (COGS), expressed as a percentage. It reveals how much profit a company makes before expenses.

Relevant Range

The range of activity within which the assumptions about fixed and variable cost behaviors hold true.

Fixed Manufacturing Cost

Costs that do not vary with the level of production, such as rent, salaries of permanent employees, and depreciation of factory equipment.