Question

Circle question. How would I convert this to standard form?

Answer 1

\[x^2+y^2+4x-4y-1=0\]

Answer 2

@jim_thompson5910 Do you think you can help me with this?

Answer 3

focus on just x^2 + 4x

what's missing to complete the square?

Answer 4

Oh, so we have to complete the square for both x and y?

Answer 5

correct

Answer 6

for x it would be 4 and for y, it would also be 4 I think.

Answer 7

yeah x^2 + 4x + 4 is a perfect square

Answer 8

so you have to add 4 to both sides to go from x^2 + 4x to x^2 + 4x + 4

Answer 9

Yes, and that can be simplified to (x+2)^2

Answer 10

I think I'm understanding this!

Answer 11

yep x^2 + 4x + 4 factors to (x+2)^2

Answer 12

I did the math and I got (x+2)^2+(y-2)^2=1

Answer 13

you forgot to add 4 to both sides. You only added to the left side

Answer 14

you're adding 2 copies of 4 actually

Answer 15

oh OOPS I forgot!

Answer 16

so it would be (x+2)^2+(y-2)^2=9

Answer 17

bingo

Answer 18

Thank you :D

Answer 19

no problem