Answer:
-12b+6c+18
Step-by-step explanation:
you just need to add the same numbers and stuff
like -4b+(-8b)=-12 and so on
hope this helps ^^
Answer:
See below.
Step-by-step explanation:
Recall the equation for a circle:
, where (h,k) is the center and r is the radius.
We need to turn the given equation into the above format. We do this by completing the square.
First, group them:

For the first section, complete the square for
:


Do the same for the second:



All together:



The center is (-9,-7).
The radius is 