The general form for the equation of a circle centre (xo, yo) and radius r is:
(x - xo)2 + (y - yo)2 = r2
Which can be rearranged into:
x2 - 2xox + y2 - 2yoy = r2 - xo2 - yo2
So a circle with centre (4, -1) and radius 8 has equations:
(x - 4)2 + (y + 1)2 = 64
x2 - 8x + y2 + 2y = 47
A unit circle is a circle of radius 1. If it's center is at the origin of an xy-coordinate system, then the equation is x (squared) + y (squared) = 1
If you mean a circle center at (3, 1) and a radius of 2 then the equation of the circle is (x-3)^2 +(y-1)^2 = 4
(x - 1)2 + (y + 1)2 = 1
The equation is: (x+1)^2 +(y+5)^2 = 36
(x + 2)2 + (y - 2)2 = 1
(x + 2)2 + (y - 2)2 = 1
The unit circle is a circle with its center at the origin and a radius of ' 1 '.
(x + 1)2 + (y + 5)2 = 36
It is (x - 1)^2 + (y - 1)^2 = 5^2
It is: (x+3)^2+(y-1)^2 = 25
The center of the circle is at (0, 0) and its radius is the square root of 1 which is 1
It is: (x-1)^2 +(y+4)^2 = 4
The centre is (3,-1) and the radius is sqrt(10).
The ' 1 ' in that equation is the radius.
Equation for a circle with any centre (h,k) is (x-h)^2 + (y-k)^2 = r^2. The equation for a circle with centre (-1,-5) and r=6 is (x+1)^2 + (y+5)^2 = 36.
The equation of a circle through the center (using "^" for power) is: x^2 + y^2 = r^2 To have the center anywhere else, say, through point (a, b), just replace "x" with "x-a" (in this case: x - 1), and "y" with "y-b" (in this case: y - -1, or y + 1).
Area of a circle = (pi) (R2)R = radius of the circle = 1/2 of its diameter
The radius of a semi-circle is the same as the radius of the circle that was cut in half. The radius of a circle is the distance from the center of the circle to any point on the circle. That's the same as 1/2 of the diameter. It's easy to measure it on a semi-circle, because you don't even need to determine where the center is. The diameter is just the length of the flat side, and the radius is half of that.
If you know the circumference (distance around the circle) then you can find the radius (distance from the center to a point on the circle) using the equation, C=2(pi)r where C is the circumference, pi is 3.1415926..., and r is the radius. Basically, if the diameter is 1 than the circumference is equal to pi.
That's a radius of the circle. Its length is 1/2 of the circle's diameter.
This equation is equal to the first one because it produces the same results, always. ... TL;DR - The circle equation is what you get when you multiply all terms from the ellipse equation by the radius. x^2/a^2 + y^2/b^2 = 1 is an ellipse equation. Well, a circle has a radius where a and b are the same.
Area of a circle = 3.14 * r2 Thus, radius, r = root of ( Area of a circle / 3.14 ) --------- equation 1 Circumference of circle = 2 * 3.14 * r Therefore, from (equation 1), Circumference = 2 * 3.14 * root of ( Area of a circle / 3.14 ). In a nutshell, first find the radius and then the circumference.
The unit circle is a circle that can be used to find trigonometric functions. The equation of the unit circle is x^2 + y^2 = 1. So it is any circle with radius 1.
The radius of a circle is equal to 1/2 of it's diameter. radius is one half of the diameter. Therefore ; r = (1/2) D
The radius is the distance from the edge to the center. Diameter is distance from one edge through the center to the other edge. The diameter is twice the radius. If the radius is 1, then twice that is 2.