Circle And System Of Circles Question 112
Question: If $ x^{2}+y^{2}+px+3y-5=0 $ and $ x^{2}+y^{2}+5x $ $ +py+7=0 $ cut orthogonally, then p is
Options:
A) $ \frac{1}{2} $
B) 1
C) $ \frac{3}{2} $
D) 2
Show Answer
Answer:
Correct Answer: A
Solution:
$ 2g_1g_2+2f_1f_2=c_1+c_2 $ for orthogonal cut.
$ \Rightarrow p( \frac{5}{2} )+p( \frac{3}{2} )=-5+7\Rightarrow p=\frac{1}{2} $ .
BETA
