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Question
Choose the correct answer for the following question.
Which of the following quadratic equations has roots 3,5?
Options
x2- 15x + 8 = 0
x2 - 8x + 15 = 0
x2 + 3x + 5 = 0
x2 + 8x - 15 = 0
Solution
The roots of the quadratic equation x2 – 8x + 15 = 0 are \[x^2 - 5x - 3x + 15 = 0\]
\[ \Rightarrow x\left( x - 5 \right) - 3\left( x - 5 \right) = 0\]
\[ \Rightarrow \left( x - 3 \right)\left( x - 5 \right) = 0\]
\[ \Rightarrow x = 3, 5\]
Hence, the correct answer is x2 - 8x + 15 = 0.
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