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Two times a number, added to the square of that number, gives 3. What could the number be?
A-1 or -3
B1 or -3
C-1 or 3
D1 or 3
Answer & Solution
Correct answer: B. 1 or -3
1. Let the number be n: n² + 2n = 3.
2. Rearrange: n² + 2n - 3 = 0.
3. Factorise: (n + 3)(n - 1) = 0.
4. So n = 1 or n = -3.
_Source: RRB Group D CEN-02/2018 PYQ, Q.14._
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