Solve the System of Equations by the Substitution Method $$\begin{aligned}x + y & = - 9 \\y & = - 4 x\end{aligned}$$

question 86

Multiple Choice

Solve the system of equations by the substitution method.
- $$\begin{aligned}x + y & = - 9 \\y & = - 4 x\end{aligned}$$

• A) \(\{ ( 3 , - 12 ) \}\)
• B) \(\{ ( 3,12 ) \}\)
• C) \(\{ ( - 3 , - 12 ) \}\)
• D) \(\{ ( - 3,12 ) \}\)

Recognize the role of aptitude tests in predicting future performance.

Understand the importance of achievement tests in assessing mastered knowledge.

Grasp the principles of test reliability and validity in psychological testing.

Comprehend the impact of external factors on test performance and standardization.

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Definitions:

Population Proportion

The ratio of members in a population who have a particular property to the total number of members in the population.

Binomial Experiment

An experiment or trial that can result in only two possible outcomes, such as success or failure, and follows the binomial distribution.

Probability of Success

The likelihood measured as a fraction or percentage, of achieving a desired outcome or positive result in an experiment or trial.

Variance

A measure of how much values in a data set differ from the mean, indicating the distribution's spread.