Circle And System Of Circles Question 355

Question: The normal to the circle $ x^{2}+y^{2}-3x-6y-10=0 $ at the point (-3, 4), is

[RPET 1986, 89]

Options:

A) $ 2x+9y-30=0 $

B) $ 9x-2y+35=0 $

C) $ 2x-9y+30=0 $

D) $ 2x-9y-30=0 $

Show Answer

Answer:

Correct Answer: A

Solution:

$ \frac{x-x_1}{x_1+g}=\frac{y-y_1}{y_1+f} $

$ \Rightarrow \frac{x+3}{-3-\frac{3}{2}}=\frac{y-4}{4-3}\Rightarrow 2x+9y-30=0 $ .