A few days ago
Anonymous

math question?

need to find the roots of the equation -2xx-4x+4 and the only way i have to find the roots is i only can foil !!!!! please help me i will vote best answer

Top 5 Answers
A few days ago
Anonymous

Favorite Answer

i can only find the root if you tell me what it equals.

and is it

-2x-4x+4=0 ??

i’ll give it a go…

-2x-4x+4=0

-2x-4x=0-4

-6x= -4

now you have to get rid of the -6

-6x/-6= -4/-6

x= 0.6

Check:

-6 x 0.6= – 3.6

round it.

-6 x 0.6= -4

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A few days ago
Irina
I believe that your equation is:

-2x^2-4x+4=0

Then you have to factor it. You can use the quadratic formula as somebody pointed out, or you can do it mentally. I’d do it like this:

1) factor out a -2

-2(x^2+2x-2)=0

2) cancel the -2 (divide by -2 on both sides)

x^2+2x-2

2) factor the expression

(x- )(x+ )=0

to fill in the blanks you know that -2 factors into 1 and 2 (one of them is negative, hence the one + sign and one -, but you don’t know which one)

The problem is, it doesn’t factor into intergers, so you have no choice but to use the quadratic formula. Right now, you have the equation in standard form:

Ax^2+Bx+C=0

A=1

B=2

C=-2

Then you plug those values into the formula:

(-B+sqrt(B^2-4AC))/2A

and

(-B-sqrt(B^2-4AC))/2A

you get two different values for x, and they are:

-1+sqrt(3)

and

-1-sqrt(3)

I hope it helped.

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A few days ago
greenwhite
You can only foil? What does that mean?

Anyways,

The roots are found when -2x^2 – 4x + 4 = 0, so

-2x^2 – 4x + 4 = 0

-2(x^2 + 2x – 2) = 0

x^2 + 2x – 2 = 0

Using the formula x = [-b +- sqrt(b^2 – 4ac)] / 2a,

x = 0.732 or x = -2.73

Therefore the roots are 0.732 and -2.73.

Hope that helps!

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A few days ago
Anonymous
Are you talking about factoring? If so, then the answer is (x+2)(x-2)

If you use the foil method, then it should be your original equation.

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A few days ago
Wylie Coyote
no solution. without the quadratic equation noted above.
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