Question 1010983: find the equation of circle passing through the points of intersection of the lines x + 3y=0 and 2x- 7y = 0 and whose center is point of intersection lines x + y +1=0 and x-2y +4=0
Answer by MathLover1(20849)   (Show Source):
You can put this solution on YOUR website! find the equation of circle passing through the points of intersection of the lines
--------------find intersection point
substitute in
=>
intersection point is at ( ,)
and whose center is point of intersection lines
----------------------------subtract
then  => =>
so, if the center of the circle is at ( , ) =( , ) and circle passes through (,) , its radius will be the distance between these two points
| Solved by pluggable solver: Distance Formula |
The first point is (x1,y1). The second point is (x2,y2)
Since the first point is (0, 0), we can say (x1, y1) = (0, 0)
So  , 
Since the second point is (-2, 1), we can also say (x2, y2) = (-2, 1)
So  , 
Put this all together to get: , , , and
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Now use the distance formula to find the distance between the two points (0, 0) and (-2, 1)
 Plug in , , , and
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Answer:
The distance between the two points (0, 0) and (-2, 1) is exactly  units
The approximate distance between the two points is about 2.23606797749979 units
So again,
Exact Distance: units
Approximate Distance:  units
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so, we have  , and  and the equation of your circle is:
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