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Question 1085811:  find the equation, in standard form, of the circle being described in each item.
 
1.diameter with endpoints (3,-5) & (6,4) 
2.center (-6,-3), through (-10,3) 
 Answer by mathmate(429)      (Show Source): 
You can  put this solution on YOUR website! Question: 
find the equation, in standard form, of the circle being described in each item. 
  
1.diameter with endpoints (3,-5) & (6,4) 
2.center (-6,-3), through (-10,3) 
  
Solution: 
Standard form of a circle is 
(x-x0)^2+(y-y0)^2=r^2 
  
1. 
Diameter end points = (3,-5), (6,4) 
Centre=((3+6)/2, (-5+4)/2))=(4.5,-0.5) 
radius, r = (1/2)sqrt((6-3)^2+(4--5)^2)=(1/2)sqrt(9+81)=(1/2)sqrt(90)=(3/2)sqrt(10), 
r²=(3/2)²(sqrt(10)²)=9/4*10=45/2 
So standard form: 
(x-4.5)²+(y+0.5)²=45/2 
  
2. radius = sqrt((-10--6)²+(3--3)²)=sqrt(16+36)=sqrt(52) 
r²=52 
standard form: 
(x--6)²+(y--3)²=52 
=> 
(x+6)²+(y+3)²=52 
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