- A5
- B4
- C6
- D3
Step-by-Step Solution
For collinear points the area of the triangle is 0: |1(k − 8) + 3(8 − 2) + 5(2 − k)| = 0 ⇒ |−4k + 20| = 0 ⇒ k = 5.
Answer: A) 5
For what value of k are the points (1, 2), (3, k) and (5, 8) collinear?
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