How to find the given point is inside or outside or lying on circle boundary ?

What is the standard equation of a circle?

(x- h)^2+(y- k)^2= r^2 

This is the general standard equation for the circle centered at (h,k) with radius r. When you center point and radius, then substitute any point (x,y)in the equation. 

• If LHS=RHS, then the point is in the boundary of the circle 
• If LHS <RHS, then the point is inside the circle   
• If LHS > RHS, then the point is outside the circle