Multiple choice

The values of k for which the roots are real and equal of the following equation $4x^2$ + kx + 9 = 0 is $k = \pm12$

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

For a quadratic equation ax^2 + bx + c = 0 to have real and equal roots, the discriminant D = b^2 - 4ac must equal 0. Here, k^2 - 4(4)(9) = 0, which simplifies to k^2 - 144 = 0, so k = +/- 12.

AI explanation

For the quadratic equation 4x^2 + kx + 9 = 0 to have real and equal roots, the discriminant (b^2 - 4ac) must be zero. Here a = 4, b = k, and c = 9, so k^2 - 4(4)(9) = 0. This simplifies to k^2 = 144, which gives k = 12 or k = -12 (written as +/- 12). Thus, the statement is True.

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