Multiple choice

If $8$ is a root of the equation $x^{2}-10x+k=0$, then the value of $k$ is :

  1. $2$
  2. $8$
  3. $-8$
  4. $16$
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D Correct answer
Explanation

If 8 is a root of x^2 - 10x + k = 0, then substituting x = 8 must satisfy the equation: 8^2 - 10(8) + k = 0. 64 - 80 + k = 0, so -16 + k = 0, which means k = 16.

AI explanation

Because 8 is a root of the quadratic equation x^2 - 10x + k = 0, substitute x = 8 into the equation. This gives 8^2 - 10(8) + k = 0, which simplifies to 64 - 80 + k = 0. Solving for k yields -16 + k = 0, so k = 16.

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