Solve the System of Linear Equations $$\left\{ \begin{array} { c } x + y + z = - 7 \\3 x + 5 y + 4 z = 8 \\3 x + 6 y + 5 z = 0\end{array} \right.$$

question 33

Multiple Choice

Solve the system of linear equations. $$\left\{ \begin{array} { c } x + y + z = - 7 \\3 x + 5 y + 4 z = 8 \\3 x + 6 y + 5 z = 0\end{array} \right.$$

• A) \(( 2,37 , - 45 )\)
• B) \(( - 1,37 , - 45 )\)
• C) \(( - 1 , - 37 , - 45 )\)
• D) \(( 1,37 , - 45 )\)
• E) \(( 1,38 , - 45 )\)

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Definitions:

Random Assignment

The allocation of study participants to different groups by chance, minimizing pre-existing differences between those groups.

True Experiments

A type of scientific experiment where the researcher manipulates one variable, and controls/randomizes the rest of the variables.

Construct Validity

The degree to which a test or instrument accurately measures the theoretical construct it is intended to measure.

One-group Pretest-posttest Design

An experimental design where a single group is measured both before and after a treatment, assessing the treatment's impact.