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In an equilateral triangle A B C , equation of the side B C is x + y - 2 = 0 and the centroid of Δ A B C is 0 , 0 . If points A , B and C are in anticlockwise order, then the equation of side A C is

Options

  1. Ay + 2 = 2 - 3 x + 2
  2. By + 2 = 2 + 3 x + 2
  3. Cy + 1 = 2 + 3 x + 1
  4. Dx + 2 = 0

Correct answer

B. y + 2 = 2 + 3 x + 2

Step-by-step solution

Foot of 0,0 on line B C is D 1,1 Because 0,0 divides A D internally in the ratio 2 : 1 Hence, by using section formula A ≡ - 2 , - 2 Slope of A C is tan ⁡ 45 ° + 30 ° = 2 + 3 Equation of A C is y + 2 = 2 + 3 x + 2

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