Multiple choice

Which of the following equations has real roots?

  1. $3x^{2}+4x+5=0$
  2. $x^{2}+x+4=0$
  3. $(x-1)(2x-5)=0$
  4. $2x^{2}-3x+4=0$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Check the discriminant (D = b^2 - 4ac) for each: A) 16 - 60 < 0. B) 1 - 16 < 0. C) (x-1)(2x-5)=0 has roots 1 and 2.5 (real). D) 9 - 32 < 0.

AI explanation

For a quadratic equation to have real roots, its discriminant (b^2 - 4ac) must be greater than or equal to zero. The equation (x - 1)(2x - 5) = 0 immediately reveals its roots as x = 1 and x = 5/2, proving they are real numbers.

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