Question

If the radius of the circle $x ^ { 2 } + y ^ { 2 } + 2 g x + 2 f y + c = 0$ be r, then it will touch both the axes, if.

• A. $g = f = r$
• B. $g = f = c = r$
• C. $g = f = \sqrt { c } = r$
• D. $g = f$ and $c ^ { 2 } = r$

Answer 1

Answer: (C)

$g = f = \sqrt { c } = r$

Answer 2

Conditions are

$g = f = r$ and $\sqrt { g ^ { 2 } + f ^ { 2 } - c } = r$ $\Rightarrow g = \sqrt { c }$ .