Answer:
The equation for a unit radius circle, centered at the origin is:
x^2 + y^2 = 1
Now, if we want to move it horizontally, you can recall to the horizontal translations:
f(x) -----> f(x - a)
Moves the graph to the right by "a" units.
A vertical translation is similar.
Then, if we want a circle centered in the point (a, b) we have:
(x - a)^2 + (y - b)^2 = 1.
Now, if you want to change the radius, we can actually write the unit circle as:
x^2 + y^2 = 1^2
Where if we set x = 0, 1 = y, this is our radius
So if we have:
x^2 + y^2 = R^2
And we set the value of x = 0, then R = y.
So our radius is R.
Then:
"A circle of radius R, centered in the point (a, b) is written as:
(x - a)^2 + (y - b)^2 = R^2
