Question

How would you complete the square with -x^2+2x-6=0?

Answer 1

-x^2+2x-6 = 0
x^2-2x = -6
x^2-2x+1 = -6 +1
(x-1)^2 = -5
x - 1 = sqrt(-5)
x = sqrt(-5) - 1
x = + or - i*sqrt(5) - 1

Answer 2

wouldn't you bring it over to the other side as a positive 6 since you're adding it?

Answer 3

Before you complete the square, it has to be in the form:
x^2 + bx = c

Answer 4

I just noticed you changed the signs to make the x positive, that makes more sense, thank you! does the x always have to be positive before completing the square?

Answer 5

Actually, let me post it a little differently so that the steps are expressed as close to the proper method as possible.

Answer 6

Alright, because I'll need it for future reference, thank you so much

Answer 7

-x^2+2x-6 = 0
-(x^2-2x +6) = 0
x^2-2x +6 = 0
x^2-2x = -6
x^2-2x+1 = -6 +1
(x-1)^2 = -5
x - 1 = sqrt(-5)
x = sqrt(-5) - 1
x = + or - i*sqrt(5) - 1

Answer 8

There we go

Answer 9

for the ending, why don't you put 1 + or - i*sqrt(5)?

Answer 10

or isn't that generally the same concept?

Answer 11

x = + or - sqrt(-5)i - 1

Answer 12

What seems to be the trouble. You're familiar with complex numbers right?

Answer 13

Oh, I see

Answer 14

x = + or - sqrt(-5)i + 1

Answer 15

I'm not perfect

Answer 16

But could the +1 go in the front? Nobodies perfect, I'm in precalc and even my teacher makes simple mistakes. Thank you a lot though this really helped!

Answer 17

x = 1 + or - i*sqrt(5)?

Answer 18

You can write it that way too

Answer 19

alright, I tried working it out on my own after I saw you extracted the - from the original equation, and came to that same conclusion. thank you! really, that made complete sense!

Answer 20

Nice