Saved Bookmarks
| 1. |
21.Acircletouches y -axis at (0, 5) and whose centre les on thecentre lies on theline 2x+y = 13 ; find the equation of the circle. |
|
Answer» Perpendicular distance of Pt. from liner=2(0)+5-13/√5=-8/√5r=8/√5..radius for centre let the X Co ordinate of point =h therefore y Co ordinate =13-2hNow centre=(h, 13-2h) we know radius therefore apply distance formula √(h-0)^2 + (13-2h-5)^2=(8/√5)solve for h and put in point of centre.. now u have centre and radius both.... and we know if (m, n) is centre and r is radius then eqn of circle is (x-m) ^2+(y-n)^2=r^2 |
|