# Circles and triangles

hello, i was wondering if anyone could help me with part c. im unsure how to do it without knowing the co-ordinates. the centre of the circle is (-2,3)
(edited 11 months ago)
Gather the x terms and y terms together and try your best to complete the square. Try to set your equation out like this:
(x+a)^2 + (y+b)^2=r^2
Where a and b are numbers
From this, you can find the coordinates
I like to make (x+a)=0 to find x, which will be your x coordinate. Do the same for (y+b) to find the y coordinate
These coordinates will be the centre of your circle
(edited 11 months ago)
thank you this is what i did for part a. its just part c i cant get my head around!!

Original post by harlz_chalamet
Gather the x terms and y terms together and try your best to complete the square. Try to set your equation out like this:
(x+a)^2 + (y+b)^2=r^2
Where a and b are numbers
From this, you can find the coordinates
I like to make (x+a)=0 to find x, which will be your x coordinate. Do the same for (y+b) to find the y coordinate
These coordinates will be the centre of your circle
Original post by izzy21234
thank you this is what i did for part a. its just part c i cant get my head around!!

Hint: What's the diameter of the circle?
Original post by _Boomerang
Hint: What's the diameter of the circle?

ah of course! thank you so much. its always the small details i miss ahaha!!