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प्रश्न
Choose the correct answer for the following question.
Out of the following equations, find the equation having the sum of its roots –5.
विकल्प
3x2 - 15x + 3 = 0
x2 - 5x + 3 = 0
x2 + 3x - 5 = 0
3x2 + 15x + 3 = 0
उत्तर
For the equation 3x2 + 15x + 3 = 0
\[\text{ Sum of roots } = \frac{- b}{a} = \frac{- 15}{3} = - 5\]
Hence, the correct answer is 3x2 + 15x + 3 = 0.
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Solution:
We need one of the solutions of the quadratic equation as 5.
Then we can take another root as any number like a positive or negative number or zero. Here I am taking another root of the quadratic equation as 2.
Then we can form a word problem as below,
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Let the age of Mita be x.
Therefore age of Smita = x – 3
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