edealfan wrote:

praetorian123 wrote:

On the x y plane, P is a point on a circle whose center is the

origin point, What's the sum of the squares of its coordinates?

A. The radius of the circle is 10

B. The sum of the coordinates is 0

A?

correct!

A.

if radius is 10, it represents the hypotenuse of a traingle whose base is the x-coordinate and height is the y coordinate

and we know for a right angled triangle,

x^2 + y^2 = 10^2 =100..so 1 is sufficient

B..

x+y =0

we can conclude anything from this statement..insufficient

So Answer A

Thanks

Praetorian