Solve x2+2X-4=0?

Answer 1

is the equation: x^2 + 2x - 4 = 0
if so, then because it doesn't seem readily factorable, you can do it this way and make it a perfect square:

(x^2 + 2x + 1) -5 = 0
(x + 1)(x + 1) = 5
take the square root:
(x+1) = plus or minus sqrt5
x = -1 plus or minus sqrt5

Answer 2

x=1

Answer 3

First: use the Quadratic Formula....
x = [- b + /- V`(b^2 - 4ac)] / 2a

*You have 3 values (coefficients) for the following variables....
a = 1 > b = 2 > c = - 4

Sec: place the values in the formula....

x = [- 2 + /- V`(2^2 - 4(1)(- 4)] / 2(1)

x = [- 2 + /- V`(4 - 4(1)(- 4)] / 2(1)

x = [- 2 + /- V`(4 - 4(- 4))] / 2(1)

x = [- 2 + /- V`(4 + 16)] / 2(1)

x = [- 2 + /- V`(20) / 2(1)

x = [- 2 + /- V`(5*2*2) / 2(1)

x = [- 2 + /- 2V`5] / 2(1)

x = [- 2 + /- 2V`5] / 2

Third: you have two solutions, one has addition-the other has subtraction....

1. x = [- 2 + 2V`5] / 2
x = (- 2/2) + (2/2)V`5
x = - 1 + V`5

2. x = [- 2 - 2V`5] / 2
x = (- 2/2) - (2/2)V`5
x = - 1 - V`5

Answer 4

Since this is not a perfect square (x + _ )^2, you will have to use the quadratic formula.
For any equation in the form: ax^2 + bx + c = 0, the formula to find the root (x) will be:
x = { -b +/- sqrt (b^2 - 4ac) } / 2a

In your equation, a=1, b=2, and c= -4

So, x = { -2 +/- sqrt (-2^2 - 4*1*-4) } / 2*1
= { -2 +/- sqrt ( 4 - (-16) } / 2
= { -2 +/- sqrt (20) } / 2
= { -2 +/- 4.4721359 } / 2
So, x = ( -2 + 4.4721359 ) / 2 = 2.4721359 / 2 = 1.2360679
and x = ( -2 - 4.4721359 ) / 2 = -6.4721359 / 2 = -3.2360679

Answer 5

You are going to have to use "Complete the Square" or the quadratic formula on this question because it does not factor easily.

I get x = -1 + or - root 5

Answer 6

Either try to factor it or use the quadratic formula. The quadratic formula works every time but is long. Look it up in your book or online

Answer 7

2x+2x=0+4
4x=4
4/4=x
x=1

Answer 8

Completing the Square is the formula you would have to use.
I got 0.449489743 as my answer but go figure.

Answer 9

x = 83

Answer 10

Use the quadratic formula...the link below shows you what this is if you are unaware