Multiple choice

If sum as well as product of roots of a quadratic equation is 9, then what is the equation?

  1. $\(x^2 + 9x - 18 = 0\)$
  2. $\(x^2 - 18x + 9 = 0\)$
  3. $\(x^2 + 9x + 9 = 0\)$
  4. $\(x^2 - 9x + 9 = 0\)$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

For a quadratic x² + bx + c = 0, sum of roots = -b and product = c. Given sum = 9, we have -b = 9, so b = -9. Given product = 9, we have c = 9. So the equation is x² - 9x + 9 = 0.