Multiple choice

Find the number of real roots in the equation, $\displaystyle { x }^{ 2 }+3x-9=0$

  1. $1$
  2. $2$
  3. $0$

  4. None
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Discriminant D = b^2 - 4ac = 3^2 - 4(1)(-9) = 9 + 36 = 45. Since D > 0, there are 2 distinct real roots.

AI explanation

The number of real roots of a quadratic equation is determined by the discriminant, D equals b squared minus 4ac. For x squared plus 3x minus 9 equals 0, the discriminant is calculated as 3 squared minus 4 times 1 times negative 9, which equals 9 plus 36, or 45. Since the discriminant is greater than zero, the equation has two distinct real roots.

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