Identify the center and radius for the following equation: x²+y²-6x+10y-15=0

Question

tkhunny · Answer

I let the last one go, but now that you've done it again, I'll venture.

"Equations" don't have either a center or a radius.  Graphs related to equations might.

Your task is to complete the square in x and in y, allowing the constant term to be what it may choose to be.

 x²+y²-6x+10y-15=0

 x² - 6x + y² +10y = 15

 x² - 6x + _____ + y² +10y + _____ = 15 + _____ + _____

Fill in the blanks!

anonymous · Answer

i'm not sure, thats what the question asks

tkhunny · Answer

Well, sorry.  Whoever wrote the question should make a better effort to speak precisely.

So, are you going to fill in the blanks?  Let's see it.

anonymous · Answer

yeah, idk thats the question on the worksheet i got, i'm not sure what to fill in :( @tkhunny

anonymous · Answer

@erin512  Hint: use (a+b)^2=a^2+b^2+2ab