+614 1. consider the circle with center (0,0) that passes through the point (-4,2)
find the radius of the circle
2.considere the circle with equation (x-1)^2+(y+7)^2=29
what is the center of the circle?
give ur answer in (a,b) form
+23252 1) To find the radius of the circle, we need to find the distance from (0,0) to (-4,,2).
Distance formula: d = sqrt( (x2 - x1)2 + (y2 - y1)2 )
= sqrt( (-4 - 0)2 + (2 - 0)2 )
= sqrt( 16 + 4)
= sqrt( 20 )
= sqrt( 4 · 5 )
= sqrt( 4 ) · sqrt( 5 )
= 2 · sqrt( 5 )
2) If the equation for a circle is in this form: (x - h)2 + (y - k)2 = r2
then the center is at (h, k) and the radius is r.
(x - 1)2 + (y + 7)2 = 29 ---> center = (1,-7) radius = sqrt( 29 )
