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Find the equation of a straight line passing through point a (3,4) and tangent to circle x square + y square = 9 Such as the title
If the tangent slope does not exist, then the distance from the center to the tangent is equal to the radius. If the slope exists, then the distance from the center to the tangent is equal to the radius. If the slope exists, then the distance from the center to the tangent is y-4 = K (x-3) kx-y + 4-3k = 0 = | 0-0 + 4-3k | / √ (K & sup2; + 1) = 3 | 3k-4 | = 3 √ (K & sup2; + 1) square
The equation of the line passing through point (1,1) and tangent to circle x2 + y2 = 2 is______ ．
Because the point (1, 1) is on the circle x2 + y2 = 2, the slope of the tangent is: − 1 − 01 − 0 = − 1. The equation of the tangent is: Y-1 = - (x-1), that is: x + Y-2 = 0, so the answer is: X + Y-2 = 0
Known circle O: (X-2) square + (y + 1) square = 1, find the equation of the line passing through point P (3,2) and tangent to circle 0!
The tangent points are (3, - 1) and (6 / 5, - 2 / 5)
Then find the straight line as x = 3, y = 4x / 3-2
RELATED INFORMATIONS
- 1. The equation of the line parallel to the line 2x-y + 1 = 0 and tangent to the circle x2 + y2 = 5 is () A. 2x-y + 5 = 0b. X2-y-5 = 0C. 2x + y + 5 = 0 or 2x + Y-5 = 0d. 2x-y + 5 = 0 or 2x-y-5 = 0
- 2. If a straight line passes through the point P (- 3, - 32), and the distance between the center of circle x2 + y2 = 25 and the straight line is 3, then the equation of the straight line is___ ．
- 3. It is known that the line L passes through the point P (- 2,5), and the slope is - 3 / 4. The equation of the circle where the line L is tangent to the point (2,2) and the center of the circle is on the line x + Y-11 = 0 is obtained Who knows? Reply
- 4. Given that two circles C1: (x + 4) 2 + y2 = 2, C2: (x-4) 2 + y2 = 2, the moving circle m is tangent to both circles C1 and C2, then the trajectory equation of the moving circle center m is () A. X = 0b. X22-y214 = 1 (x ≥ 2) C. x22-y214 = 1D. X22-y214 = 1 or x = 0
- 5. Given circle C1: (x + 3) ^ 2 + y ^ 2 = 1 and circle C2: (x-3) ^ 2 + y ^ 2 = 9, the moving circle m is circumscribed with circle C1 and C2 at the same time The orbit equation of moving circle center M
- 6. If the parabola C1 and the parabola C2: y ^ 2 = - 4x are symmetric with respect to the straight line x + y = 2, then the focal coordinate of the parabola C1 is
- 7. Let the equation of the ellipse be x square + y square / 4 = 1, the straight line passing through M (0,1) intersects the ellipse at two points AB, O is the coordinate origin, Op vector = 1 / 2 (OA vector + ob vector). When l rotates around point m, the trajectory equation of the moving point P is obtained
- 8. The linear equation with ellipse (x ^ 2 / 9) + (y ^ 2 / 4) = 1 intersecting at two points a and B, and the midpoint of line AB is m (1,1) is, using the point difference method
- 9. If the midpoint of line a and B is (1,1), then the equation of L is?
- 10. It is known that m (4,2) is the midpoint of line AB cut by ellipse x2 + 4y2 = 36, then the equation of line L is______ ．
- 11. It is known that the ellipse takes the symmetry axis as the coordinate axis, and the major axis is three times of the minor axis, and passes through the point (3,0)
- 12. Find the equation of the circle which passes through the point m (3, - 1) and the circle C: x2 + Y2 + 2x-6y + 5 = 0 and is tangent to the point n (1,2). Why can't we use the equation of the circle system? Isn't there an intersection point between the tangent and the circle?
- 13. A beam of light is emitted from a (- 2,3), reflected by x-axis, and tangent to the circle C (x-3) 2 + (Y-2) 2 = 1. The equation of the straight line of the reflected light is obtained Method 1: the symmetrical point of point a about the x-axis is on the line where the reflected light is located PS: it's a clue to the title, but I'm not good at it
- 14. Find the tangent equation of the circle x 2 + y 2 = 4 from point a (2,4)
- 15. Tangent equation of P (- 5, - 2) and circle x ^ 2 + y ^ 2 = 25 RT
- 16. Find the tangent equation passing through point a (- 4,3) and tangent to circle (x + 1) square + (y + 1) square = 25 Find the tangent equation passing through point a (- 4,3) and tangent to circle (x + 1) square + (y + 1) square = 25
- 17. If the line x + y = C is tangent to the circle X & # 178; + Y & # 178; = 2, then C = () 3Q
- 18. Given that the moving circle is circumtangent to the circle (x + 2) 2 + y2 = 4 and tangent to the straight line x = 2, the trajectory equation of the center P of the moving circle is obtained
- 19. The equation of the circle whose center is C (3, - 5) and tangent to the line x-7y + 2 = 0 is______ ．
- 20. Given the circle C: X & # 178; + Y & # 178; = 4, the tangent equation of the circle passing through the point (- 2,1) is? What is the answer and the difference between the tangent equation and the ordinary equation?