InterviewSolution
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InterviewSolution
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tIND K So THAT THE AREA OFAe is 2 u OVITS WITH VERTICES |
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Answer» A (1,-1), B(-4,2k) and C(-k,-5) ArΔABC = 1/2 [x1 (y2-y3) + x2(y3-y1) + x3 (y1-y2) ] 24 = 1/2 [1(2k+5) + -4(-5+1) + -k(-1-2k) 24 = 1/2 [2k+5 + 16 +(k+2k²)] 24 = 1/2 (2k+5+16+k+2k²) 24 = 1/2 (2k² +3k+21) 48 = 2k² +3k + 21 2k²+3k-27 = 0 2k² + 9k - 6k - 27 = 0 or 2k² -6k + 9k - 27 =0 2k(k-3) + 9(k-3) = 0 (2k+9) (k-3) = 0 ∴ k = -9/2 or 3 |
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