Determine Which of the Following Systems of Equations Is in Row-Echelon

question 94

Multiple Choice

Determine which of the following systems of equations is in row-echelon form. System I: $\left\{ \begin{aligned}x - 8 y + 6 z & = 2 \\y - 7 z & = - 19 \\z & = 17\end{aligned} \right.$ System II: $$\left\{ \begin{aligned}x - 6 y - 8 z & = 2 \\2 y + 5 z & = - 1 \\z & = - 3\end{aligned} \right.$$ System III: $$\left\{ \begin{aligned}x - 4 y - z & = 20 \\y + 3 z & = 14 \\z & = 9\end{aligned} \right.$$

• A)None of the systems are in row-echelon form.
• B)Only system I is in row-echelon form.
• C)Only systems I and III are in row-echelon form.
• D)Only systems I and II are in row-echelon form.
• E)Only systems II and III are in row-echelon form.

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Definitions:

Cognitive Stages

The phases of cognitive development proposed by theorists like Jean Piaget, marking the progression of thought processes and abilities from infancy through adulthood.

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Psychological capabilities that are required for processing information, such as attention, memory, reasoning, and problem-solving.

Concrete Operational Stage

A phase of cognitive development in children, proposed by Piaget, where they are able to think logically about objects and events.

Cognitive Development

the study of how thinking, problem solving, and intelligence evolve and change throughout the lifespan.