## anonymous one year ago Solve: x^2+8x-8=0 A. {-4, pos./neg. sq. root of 6} B. {4, pos./neg. sq. root of 12} C. {-4, 2 times pos./neg. sq. root of 12} D. {-4, 2 times pos./neg. sq. root of 6}

1. anonymous

@pooja195

2. anonymous

@mathmate

3. IrishBoy123

are you learning how to complete a square? $$x^2+8x-8 = 0$$ $$(x+4)^2-16-8 = 0$$ ???? or to plug numbers into this (same thing) $$\frac{- b \pm \sqrt{b^2 - 4ac}}{2a}$$ ?? or to draw curves?

4. anonymous

it just says to solve it and I don't know how. it's probably completing the square.

5. IrishBoy123

ok!, well here you go: https://www.mathsisfun.com/algebra/completing-square.html suggest you have a crack at this and report back good luck :p

6. mathmate

@yayah2001 The answer choices are all wrong. The way they are written, there are 3 roots, which is impossible for a quadratic equation. You may want to check if there is a typo, perhaps the comma (,) should be a plus sign or something else.

7. anonymous

I got the answer. thanks for the help!

8. IrishBoy123

the answer *is* in there :p

9. mathmate

@IrishBoy123 I am not worried about the answer. The OP should understand that there is a difference between {-4, 2 times $$\pm\sqrt{6}$$} which implies 3 roots, and {-4+ 2 times $$\pm\sqrt{6}$$} which means there are two roots. He may have chosen the right letter choice, but real life does not exist in multiple choices, sigh!

10. anonymous

by 2 times I meant multiplication

11. triciaal

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12. mathmate

@yayah2001 You may not have noticed it, it's between the comma and the + sign that I was referring to.

13. anonymous

thanks for the help, @mathmate, I already have the answer. but, thanks for helping.