Solve by Completing the Square $$z ^ { 2 } + 8 z - 5 = 0$$

question 56

Multiple Choice

Solve by completing the square.
- $$z ^ { 2 } + 8 z - 5 = 0$$

• A) \(- 4 \pm 2 \sqrt { 21 }\)
• B) \(- 1 \pm \sqrt { 21 }\)
• C) \(4 + \sqrt { 21 }\)
• D) \(- 4 \pm \sqrt { 21 }\)

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Definitions:

Field Experiment

An experiment conducted in a real-world setting.

Quasi-Experiment

An empirical study used to estimate the causal impact of an intervention, lacking the full random assignment of participants to conditions or orders.

Debriefed

The process of providing a detailed explanation or information to participants after an experiment or significant event has concluded.

Confounding

Occurs when the effects of two variables cannot be separated.