please help w/ completing the square: x^2+y^2+8x+15=0

[georgebaseball]

I have to solve 30 exercises of this type. If somebody could please give me a hand with this one, I can use your help as a guide to solve the other exercises. The instructions say:

Use the method of completing the square to write each equation in standard form.

The first equation is:

x^2 + y^2 + 8x + 15 = 0

Thank you!

 

[arthur ohlsten]

x^2+y^2+8x+15=0 group the x and y terms
[x^2+8x ] +y^2 +15=0 complete the square by adding and subtracting 1/2
the x coefficient squared
[x^2+8x+16]+y^2 -16 +15=0
[x+4]^2+y^2=1 a circle centered at -4,0 radius 1

Arthur

 

[georgebaseball]

thank you so much arthur