Co-ordinate

please help me proof this one....The area formed by the three intersecting line

y=m₁x + c₁, y=m₂x + c₂, y=m₃x + c₃.......is

12 Î£[ (c₁-c₂)²(m₁-m₂)]

how to proof this one???

2 Answers

106

Asish Mahapatra ·2011-06-10 05:15:48

if (x₁,y₁), (x₂,y₂) and (x₃,y₂) are the three vertices of a triangle,

area of the triangle = 12[x₁(y₂ - y₃) + x₂(y₃ - y₁) + x₃(x₁ - x₂)]

(X class result)

all you have to do now is to find the three points of intersection which should be pretty easy

I used to hate these type of things always! :P

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