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

Answer 1

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.