Multiple choice

In which of the quadratic equations, the roots are equal.

  1. $x^2-8x+16=0$
  2. $4x^2-8x+9=0$
  3. $2x^2-3x+4=0$
  4. $3x^2-2x+1=0$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A quadratic equation has equal roots if the discriminant D = b^2 - 4ac = 0. For x^2 - 8x + 16 = 0, D = (-8)^2 - 4(1)(16) = 64 - 64 = 0.

AI explanation

A quadratic equation ax^2 + bx + c = 0 has equal roots if its discriminant, given by b^2 - 4ac, is equal to zero. For the equation x^2 - 8x + 16 = 0, the discriminant is calculated as (-8)^2 - 4(1)(16) = 64 - 64 = 0. Because the discriminant is zero, this equation has equal real roots.

Keep practicing — related questions