What is the discriminant of x² − 4x + 5, and what does it tell you?
Answer and explanation
Correct answer: B. −4, so there are no real roots because the discriminant is negative
- Step 1: Compute D = b² − 4ac = 16 − 20. Step 2. D = −4 is negative, so the quadratic never crosses the x-axis. Answer: D = −4, no real roots. Why not the others: A positive D gives two roots and D = 0 gives one repeated root.
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