co-ordinate geometry

prove that the straight lines ax+(b+c)y+d=0,bx+(c+a)y+d=0 and cx+(a+b)y+d=0 are concurrent?

1 Answers

The determinant will be 0 since the constant term (d) is same in all three

So they r concurrent

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∑ ∑ ∑ ∑ ∑ ∮ ∮ ∮ ∮ ∮ ∏ ∏ ∏ ∏ ∏ ∐ ∐ ∐ ∐ ∐

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