CMA Foundation · Fundamentals of Business Mathematics and Statistics · Quadratic Equations
Using the quadratic formula, the roots of 2x^2 - 5x - 12 = 0 are:
The roots are 4 and -3/2. The discriminant is 25+96=121 with square root 11, so x=(5±11)/4, giving 4 and -1.5. The product of roots, -6, equals c/a, confirming the result.
- A4 and -3/2Correct
- B-4 and 3/2
- C3 and -4/2
- D12 and -1/2
Explanation
Discriminant = 25 + 96 = 121, root = 11. x = (5 ± 11)/4 gives 16/4 = 4 and -6/4 = -3/2. Check: product = -6 = c/a = -12/2. The option -4 and 3/2 has the signs reversed.
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