Circle And System Of Circles Question 283
Question: Equation of radical axis of the circles $ x^{2}+y^{2}-3x-4y+5=0 $ , $ 2x^{2}+2y^{2}-10x $ $ -12y+12=0 $ is
[RPET 2003]
Options:
A) $ 2x+2y-1=0 $
B) $ 2x+2y+1=0 $
C) $ x+y+7=0 $
D) $ x+y-7=0 $
Show Answer
Answer:
Correct Answer: A
Solution:
Circles are, $ S_1=x^{2}+y^{2}-3x-4y+5=0 $ ….. (i) and $ S_2=2x^{2}+2y^{2}-10x-12y+12=0 $ or $ S_2=x^{2}+y^{2}-5x-6y+6=0 $ ….. (ii)
$ \therefore $ Equation of radical axis is $ S_1-S_2=0 $
$ \Rightarrow $ $ 2x+2y-1=0 $ .
BETA
