One of the circle that through points (1,5) and (4,1) and touch the y-axis, has radius?

any clue?

Question

One of the circle that through points (1,5) and (4,1) and touch the y-axis, has radius?

any clue?

tkhunny · Answer

One step on your way might be finding a hint about the center of the circle.  Write the equation of the line connecting the two points.  THEN, write the equation of the perpendicular bisector of the line segment between tht etwo points.  The center of the circle MUST be on this line.  Why?

chihiroasleaf · Answer

because the distance from both points to the radius is the same (?)

tkhunny · Answer

Fair enough.  What is the equation of that line?

chihiroasleaf · Answer

-3x+4y=4.5 (?)

tkhunny · Answer

Better try that again.

Slope is -4/3 passing through (5/2,3)

chihiroasleaf · Answer

wait, what line do you ask? 
the line that through two points or the equation of  the perpendicular line?
It's the equation of the perpendicular line that I write ;D

tkhunny · Answer

The perpendicular bisector of the line segment joining the two given points.

chihiroasleaf · Answer

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