question_answer

 The equation of the circle touching \[x=0,y=0\] and \[x=4\] is                                                     [UPSEAT 2004]

A)            \[{{x}^{2}}+{{y}^{2}}-4x-4y+16=0\]

B)            \[{{x}^{2}}+{{y}^{2}}-8x-8y+16=0\]

C)            \[{{x}^{2}}+{{y}^{2}}+4x+4y+4=0\]                          

D)            \[{{x}^{2}}+{{y}^{2}}-4x-4y+4=0\]

Correct Answer: D

Solution :

           \[{{(x-2)}^{2}}+{{(y-2)}^{2}}=4\]                    \[{{x}^{2}}+4-4x+{{y}^{2}}+4-4y=4\]                                                        \[{{x}^{2}}+{{y}^{2}}-4x-4y+4=0\].