- A
- B
- C
- D
Step-by-Step Solution
Expand . The terms cancel, leaving , which is linear. The other three are all quadratic: becomes (it only LOOKS non-standard until you expand), becomes , and is already in standard form with .
Answer: C)
Which of the following is NOT a quadratic equation?
Class 10Quadratic EquationsAlgebra — Quadratics
Key idea: Method 3: The quadratic formula
The general solution to (any quadratic):
** = [− ± √] /
Derivation: complete the square on in full generality.
**Always works** when ≥ 0. When , no real roots exist (complex roots only — Class 11 territory).
**Example**: = (5 ± 1) / 6 → or 2/3.
** = [− ± √] /
Derivation: complete the square on in full generality.
**Always works** when ≥ 0. When , no real roots exist (complex roots only — Class 11 territory).
**Example**: = (5 ± 1) / 6 → or 2/3.
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