For 3x^2 + 5x - 2 = 0 a student writes x = 5 ± √496 and reports the roots 2 and -1/3. Which correction is needed?

Question

Accepted Answer

The numerator must begin with -b = -5, so the roots are 1/3 and -2. D = 25 - 4(3)(-2) = 25 + 24 = 49 is correct, and 2a = 6 is correct. The slip is the sign of the first term: it is -b = -5. x = -5 ± 7/6 = 1/3 or -2 — the negatives of what was reported.

For $3 x^{2} + 5 x - 2 = 0$ a student writes $x = \frac{5 \pm 49}{6}$
and reports the roots 2 and $- \frac{1}{3}$ . Which correction is needed?

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More Class 10 The Quadratic Formula practice

For 3x2+5x−2=0 a student writes x=65±49​​and reports the roots 2 and −31​. Which correction is needed?

Step-by-Step Solution

Master this chapter in 30 minutes a day.

More Class 10 The Quadratic Formula practice

For $3 x^{2} + 5 x - 2 = 0$ a student writes $x = \frac{5 \pm 49}{6}$
and reports the roots 2 and $- \frac{1}{3}$ . Which correction is needed?