Find circle passing through two points and center lying on a line

AI Thread Summary
To find the equation of a circle that passes through points A(2,2) and B(5,3) with its center on the line y = x + 1, two equations can be derived from the circle's standard form using the coordinates of points A and B. This results in two equations involving the center coordinates (h, k) and the radius r. To solve for the center, one can determine the midpoint of segment AB and the slope of line AB, then find the slope of the perpendicular bisector. The intersection of this bisector with the line y = x + 1 will provide the center of the circle. The discussion emphasizes using geometric properties and relationships to solve for the circle's parameters.
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Homework Statement



Find the equation of a circle that passes through the points A(2,2) and B(5,3) and has its centre on the line y = x +1

Homework Equations



(x-h)^2 + (y-k)^2 = r^2

The Attempt at a Solution



can get 2 equations knowing the 2 points the circle passes through but still have 3 variables and am not sure how to use the equation for the centre

(2-h)^2 + (2-k)^2 = r^2

(5-h)^2 + (3-k)^2 = r^2


How do I solve from here?
 
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What is h in terms of k?
 
Any perpendicular bisector of a chord is a radius- i.e. passes through the center of the circle.

What is the center point of the interval AB? What is the slope of the line AB? What is the slope of a line perpendicular to that? What is the equation of the perpendicular bisector of AB? Where does that line intersect y= x+1?
 
thanks!
 
I tried to combine those 2 formulas but it didn't work. I tried using another case where there are 2 red balls and 2 blue balls only so when combining the formula I got ##\frac{(4-1)!}{2!2!}=\frac{3}{2}## which does not make sense. Is there any formula to calculate cyclic permutation of identical objects or I have to do it by listing all the possibilities? Thanks
Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks
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