The equation of the circle with (3,4) as the center and passing through the origin is

The equation of the circle with (3,4) as the center and passing through the origin is

Building owner:
The radius is equal to (3 ^ 2 + 4 ^ 2) = 5 under the root sign, so the equation is written as (x-3) ^ 2 + (y-4) ^ 2 = 25

The equation of a circle whose center is the coordinate origin and radius is 3 is

x2+Y2=9

Through the origin, the center of the circle is on the negative half axis of the x-axis, and the equation of the circle with radius equal to 2 is______ ．

Let the center of the circle be (a, 0) (a < 0), the radius of the circle be 2, then the equation of the circle is (x-a) 2 + y2 = 4, and ∵ the origin o (0, 0) is on the circle, ∵ 0-A) 2 + 02 = 4, then A2 = 4, and a = - 2 (rounding). Thus the equation of the circle is (x + 2) 2 + y2 = 4. So the answer is: (x + 2) 2 + y2 = 4