Answers

2015-11-03T18:05:27+05:30
 x1(y2 - y3) + x2(y3 - y1) + x3(y1 - y2) = 0

5(k - (-2)) + 7 ((-2) - 4) + 9 (4 - k) = 0

5(k + 2) +7 (-6) + 9(4-k) = 0

5k + 10 + (-42) + 36 - 9k =0

-4k + 46 -42 = 0

-4k + 4 = 0
  
 -4k = -4

k = -4/ -4

k=1

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