The equation is
(x - h)2 + (y - v)2 = r2
x2 + y2 = 25
x2 + y2 = 25
x2 + y2 =144
x2 + y2 = 400
x² + y² = 225.
The radius of the circle decreases when you make the circle smaller.
The Radius
Standard equation for a circle centred at the origin is x2 + y2 = r2 where r is the radius of the circle. If you increase the size of the circle then the radius must increase, so r2 will be larger. eg a circle of radius 2 has the equation x2 + y2 = 4, if the radius increases to 3 then the equation becomes x2 + y2 = 9
You should increase the radius in the standard equation of a circle centered at the origin. The general form is ( x^2 + y^2 = r^2 ), where ( r ) is the radius. By increasing ( r ), you extend the distance from the center to any point on the circle, making it larger.
It is x^2 + y^2 = r^2
If that equals 16 then the radius is 4
The equation is: x2+y2 = radius2
x2 + y2 = 25
x2 + y2 = 25
x2 + y2= 16
x2 + y2 = 49
x2 + y2 = 36