
Keep working on it,
it's 1.30 am here, so it's my naptime.
Remember the following though.
When you write the equation of a line, the x and y values are the coordinates of all of the points on the line.
A different x will go with a different y.
When you have 2 line equations, as in these cases,
once you solve the simultaneous equations,
you find the only point on both lines, because only those x and y coordinates are on both lines.
This is why you need to first write the equations of the lines that the orthocentre and circumcentre are on, before you solve the simultaneous equations.

Ok,
two perpendicular bisectors, already written are....
Hence...
Also...
Since
then
Now, work out this x and use it to find y.

ok
this is still about the circumcenter, right?
if it is, thanks.

is this right?

It sure does,
now you will have no bother finding y.
If you go back over all this and write it out neatly for yourself,
with the diagrams of the triangles and the lines,
understanding the geometry, point coordinate geometry,
and how the geometry is expressed in algebra,
you will have learned quite a lot through your efforts,
and it will be quite memorable for you.
Good job!

hi there again
can u finish the problem for me?
i'm confused on the y.

Maybe, you've worn yourself out for the day!
Ok, but promise me you'll do it all again from scratch soon???
If you do, you will know why I asked.
You are probably confused about the y because you don't know which equation to put it in.
You will get the same y if you put the x coordinate of the circle centre into either perpendicular bisector....
The circle centre x coordinate is 46.7
Therefore
so
Or
so


no wait 20.624 equals 3.4
while 20.632= 11.3
O_O

Hello everyone
I think it's time we drew this to a close. Here's what I got for the circumcentre, continuing from the point that I and red_dog had left at.
Solving the equations simultaneously, it's not difficult, but the arithmetic is tedious:
And:
Multiply (1) by and (2) by :
Subtract:
(to 2 d.p.)
Substitute into (1);
(to 2 d.p.)
So the circumcentre is . Check that I haven't made any mistakes with the arithmetic.
Grandad
