Question

Which of the following is not a quadratic equation
3 + x + x² = 0
x² – 9 = 0
(x² + 2x)² = x + 3​

Answer 1

The third one is not a quadratic equation as when the bracket will be opened x raised to 2 will become x raised to 4.
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Hope this helped

Answer 2

Answer:

Hope it helps you This is the correct answer