question_answer

The locus of the centres of all circles of given radius r, in the same planes, passing through a fixed point is

A)  A point          

B)         A circle  

C)  A straight line                  

D)  Two straight lines

Correct Answer: B

Solution :

 The locus of the centres of all circles of given radius r, in the same plane, passing through a fixed point \[P({{x}_{1}},{{y}_{1}})\] is ? 'A circle, whose radius is r and centre is the given fixed point \[P(x,y)'\] Its equation will be \[{{(x-{{x}_{1}})}^{2}}+{{(y-y)}^{2}}={{r}^{2}}\]