SOLUTION: Let P(-3,6) and Q(10,1) be two points in the coordinate plane Find an equation of the circle that contains P and Q and whose center is the midpoint of the segment PQ

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Question 730942: Let P(-3,6) and Q(10,1) be two points in the coordinate plane
Find an equation of the circle that contains P and Q and whose center is the midpoint of the segment PQ

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
The standard equation of a circle with center C(h,k) and radius r is as follows:
%28x-h%29%5E2+%2B+%28y+-k%29%5E2+=+r%5E2
so, we need to find h,+k, and r
since the circle that contains P and Q , the distance between them is equal to diameter of the circle:
Solved by pluggable solver: Distance Formula


The first point is (x1,y1). The second point is (x2,y2)


Since the first point is (-3, 6), we can say (x1, y1) = (-3, 6)
So x%5B1%5D+=+-3, y%5B1%5D+=+6


Since the second point is (10, 1), we can also say (x2, y2) = (10, 1)
So x%5B2%5D+=+10, y%5B2%5D+=+1


Put this all together to get: x%5B1%5D+=+-3, y%5B1%5D+=+6, x%5B2%5D+=+10, and y%5B2%5D+=+1

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Now use the distance formula to find the distance between the two points (-3, 6) and (10, 1)



d+=+sqrt%28%28x%5B1%5D-x%5B2%5D%29%5E2+%2B+%28y%5B1%5D+-+y%5B2%5D%29%5E2%29


d+=+sqrt%28%28-3+-+10%29%5E2+%2B+%286+-+1%29%5E2%29 Plug in x%5B1%5D+=+-3, y%5B1%5D+=+6, x%5B2%5D+=+10, and y%5B2%5D+=+1


d+=+sqrt%28%28-13%29%5E2+%2B+%285%29%5E2%29


d+=+sqrt%28169+%2B+25%29


d+=+sqrt%28194%29


d+=+13.9283882771841

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Answer:


The distance between the two points (-3, 6) and (10, 1) is exactly sqrt%28194%29 units


The approximate distance between the two points is about 13.9283882771841 units



So again,


Exact Distance: sqrt%28194%29 units


Approximate Distance: 13.9283882771841 units




so, diameter d=13.9...=>...r=13.9%2F2...=>...r=6.95
now find midpoint:
Solved by pluggable solver: Midpoint


The first point is (x1,y1). The second point is (x2,y2)


Since the first point is (-3, 6), we can say (x1, y1) = (-3, 6)
So x%5B1%5D+=+-3, y%5B1%5D+=+6


Since the second point is (10, 1), we can also say (x2, y2) = (10, 1)
So x%5B2%5D+=+10, y%5B2%5D+=+1


Put this all together to get: x%5B1%5D+=+-3, y%5B1%5D+=+6, x%5B2%5D+=+10, and y%5B2%5D+=+1

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Finding the x coordinate of the midpoint: Add up the corresponding x coordinates x1 and x2 and divide that sum by 2


X Coordinate of Midpoint = %28x%5B1%5D%2Bx%5B2%5D%29%2F2


X Coordinate of Midpoint = %28-3%2B10%29%2F2


X Coordinate of Midpoint = 7%2F2


X Coordinate of Midpoint = 3.5



So the x coordinate of the midpoint is 3.5


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Finding the y coordinate of the midpoint: Add up the corresponding y coordinates y1 and y2 and divide that sum by 2


Y Coordinate of Midpoint = %28y%5B1%5D%2By%5B2%5D%29%2F2


Y Coordinate of Midpoint = %286%2B1%29%2F2


Y Coordinate of Midpoint = 7%2F2


Y Coordinate of Midpoint = 3.5


So the y coordinate of the midpoint is 3.5



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Summary:


The midpoint of the segment joining the two points (-3, 6) and (10, 1) is (3.5, 3.5).


So the answer is (3.5, 3.5)




center is (3.5, 3.5)=(h,+k)...so h=3.5 and k=3.5
%28x-h%29%5E2+%2B+%28y+-k%29%5E2+=+r%5E2...plug in h=3.5,k=3.5, and r=6.95
your equation is:

%28x-3.5%29%5E2+%2B+%28y+-3.5%29%5E2+=+6.95%5E2