Find the equations of circles determined by the following conditions and draw their figures (1) The center of the circle is m (3, - 5) and tangent to the line x-7y + 2 = 0 (2) The center of the circle is on the y-axis, the radius length is 5, and it is tangent to the line y = 6

Find the equations of circles determined by the following conditions and draw their figures (1) The center of the circle is m (3, - 5) and tangent to the line x-7y + 2 = 0 (2) The center of the circle is on the y-axis, the radius length is 5, and it is tangent to the line y = 6

(1) So, the key is to find the tangent point, and then find the distance from the center of the circle to the tangent point, that is, R. or, directly find the distance from the center of the circle to the straight line. Obviously, the second method is simpler. The formula of the distance from the point to the straight line is d = ｜ ax + by + C ｜ / √ (a ^ 2 + B ^ 2)