co-ordinate geometry

if ab+bc+ca=0,show that the lines x/a+y/b=1/c, x/b+y/c=1/a, and x/c+y/a=1/b are concurrent?

1 Answers

From ab+bc+ca=0 v get that 1/a +1/b + 1/c = 0

Taking det we get Î” = 1/a 1/b 1/c = 0 1/b 1/c = 0

1/b 1/c 1/a 0 1/c 1/a

1/c 1/a 1/b 0 1/a 1/b

Hence the lines r concurrent

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