Multiple choice

If one zero of the quadratic polynomial x2+3x + k is 2, then the value of k is

  1. 10

  2. -10

  3. 5

  4. -5
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

If 2 is a zero of x^2 + 3x + k, then f(2) = 0. 2^2 + 3(2) + k = 0. 4 + 6 + k = 0. 10 + k = 0, so k = -10.

AI explanation

If 2 is a zero of the polynomial x2 + 3x + k, you can substitute x = 2 directly into the equation. This yields (2)2 + 3(2) + k = 0, which simplifies to 4 + 6 + k = 0. Solving this linear equation gives 10 + k = 0, meaning the value of k is -10.

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