Sana solves x^2 - 8x + 12 = 0, finds D = 16, and reports the single answer x = 6. What has she missed?

Question

Accepted Answer

She dropped the ± — the second root is x = 8 - 4/2 = 2. D = 64 - 48 = 16 is right, √D = 4. The ± must be used both ways: x = 8 + 4/2 = 6 and x = 8 - 4/2 = 2. A positive discriminant always yields two distinct roots.

Sana solves $x^{2} - 8 x + 12 = 0$ , finds $D = 16$ , and reports the single answer $x = 6$ .
What has she missed?

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More Class 10 The Quadratic Formula practice

Sana solves x2−8x+12=0, finds D=16, and reports the single answer x=6.What has she missed?

Step-by-Step Solution

Master this chapter in 30 minutes a day.

More Class 10 The Quadratic Formula practice

Sana solves $x^{2} - 8 x + 12 = 0$ , finds $D = 16$ , and reports the single answer $x = 6$ .
What has she missed?