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nia008
Oct 20, 2011, 08:24 PM
what is the equation of circle whose center is (-3,-2) and passes through points(2,1)

ahmad81
Oct 21, 2011, 03:01 AM
The genera formula for circle equation is (x-a)^2+(x-b)^2=r^2
such that (a,b) center of the circle and r is the radius. In this question there is no radius given.but we have the center and one point passes. Then the equation will be
(x-(-3))^2+(y-(-2))^2=r^2... (1)
now take the point (2,1), substitution x=2 and y=1 in(1), we have
(5)^2+((3)^2=r^2
25+9=r^2
25=r^2
r=5, we can't take another value for r because it is in negative and we deal with distance, then r=5.
substitution r=5 in (1), we have
(x-(-3))^2+(y-(-2))^2=5^2
(x+3)^2+(y+2)^2=25
Best wishes
Mr.Ahmad Rababah
Najran University

ebaines
Oct 21, 2011, 05:47 AM
Ahmad: welcome to the AMHD web site. Please be aware that our policy here is to not provide complete solutions for homework problems but rather simply to provide guidance where it's needed to help the student along. Please see this announcement:
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ahmad81
Oct 21, 2011, 08:08 AM
Can't see anything

ebaines
Oct 21, 2011, 08:23 AM
can't see anything

Try this link:

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