0=x^2-x-4

Simple and best practice solution for 0=x^2-x-4 equation. Check how easy it is, and learn it for the future. Our solution is simple, and easy to understand, so don`t hesitate to use it as a solution of your homework.

If it's not what You are looking for type in the equation solver your own equation and let us solve it.

Solution for 0=x^2-x-4 equation:


Simplifying
0 = x2 + -1x + -4

Reorder the terms:
0 = -4 + -1x + x2

Solving
0 = -4 + -1x + x2

Solving for variable 'x'.

Combine like terms: 0 + 4 = 4
4 + x + -1x2 = -4 + -1x + x2 + 4 + x + -1x2

Reorder the terms:
4 + x + -1x2 = -4 + 4 + -1x + x + x2 + -1x2

Combine like terms: -4 + 4 = 0
4 + x + -1x2 = 0 + -1x + x + x2 + -1x2
4 + x + -1x2 = -1x + x + x2 + -1x2

Combine like terms: -1x + x = 0
4 + x + -1x2 = 0 + x2 + -1x2
4 + x + -1x2 = x2 + -1x2

Combine like terms: x2 + -1x2 = 0
4 + x + -1x2 = 0

Begin completing the square.  Divide all terms by
-1 the coefficient of the squared term: 

Divide each side by '-1'.
-4 + -1x + x2 = 0

Move the constant term to the right:

Add '4' to each side of the equation.
-4 + -1x + 4 + x2 = 0 + 4

Reorder the terms:
-4 + 4 + -1x + x2 = 0 + 4

Combine like terms: -4 + 4 = 0
0 + -1x + x2 = 0 + 4
-1x + x2 = 0 + 4

Combine like terms: 0 + 4 = 4
-1x + x2 = 4

The x term is x.  Take half its coefficient (0.5).
Square it (0.25) and add it to both sides.

Add '0.25' to each side of the equation.
-1x + 0.25 + x2 = 4 + 0.25

Reorder the terms:
0.25 + -1x + x2 = 4 + 0.25

Combine like terms: 4 + 0.25 = 4.25
0.25 + -1x + x2 = 4.25

Factor a perfect square on the left side:
(x + 0.5)(x + 0.5) = 4.25

Calculate the square root of the right side: 2.061552813

Break this problem into two subproblems by setting 
(x + 0.5) equal to 2.061552813 and -2.061552813.

Subproblem 1

x + 0.5 = 2.061552813 Simplifying x + 0.5 = 2.061552813 Reorder the terms: 0.5 + x = 2.061552813 Solving 0.5 + x = 2.061552813 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-0.5' to each side of the equation. 0.5 + -0.5 + x = 2.061552813 + -0.5 Combine like terms: 0.5 + -0.5 = 0.0 0.0 + x = 2.061552813 + -0.5 x = 2.061552813 + -0.5 Combine like terms: 2.061552813 + -0.5 = 1.561552813 x = 1.561552813 Simplifying x = 1.561552813

Subproblem 2

x + 0.5 = -2.061552813 Simplifying x + 0.5 = -2.061552813 Reorder the terms: 0.5 + x = -2.061552813 Solving 0.5 + x = -2.061552813 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-0.5' to each side of the equation. 0.5 + -0.5 + x = -2.061552813 + -0.5 Combine like terms: 0.5 + -0.5 = 0.0 0.0 + x = -2.061552813 + -0.5 x = -2.061552813 + -0.5 Combine like terms: -2.061552813 + -0.5 = -2.561552813 x = -2.561552813 Simplifying x = -2.561552813

Solution

The solution to the problem is based on the solutions from the subproblems. x = {1.561552813, -2.561552813}

See similar equations:

| -9k=79 | | 88t-23=-15 | | 5m+m=150 | | n/4=-7 | | 3x*(x+2)=0 | | 6x-15=2x+20 | | -(8y+3)-(-7y-4)=0 | | -x/4=9 | | 0=x^2+4x-1 | | 6(2t+3)=3(11t+11) | | 6(-5x-8)=-6(6x-7) | | 0=x^2+7x+10 | | 4z-7-5z=-8 | | x^2-y^2+3x=0 | | 4t-5+8t=7(t+6) | | 30x(2x^2-1)=0 | | -8x+6+5x-1=3-14x-7+10x | | 5(y+3)=30 | | 4y+16=4 | | 5(x-1)+2=2x+11 | | -2(7-7x)=84 | | 2xy-3y=0 | | 7x+5=3x+53 | | 18+2w=7w-13 | | 2(x-1)+4=14 | | 9+3r-5=9r+13-5r | | 7(-6x+6)=42 | | 2x-4=-6x+68 | | 9-7x-6x=-30 | | 5x-3=-3x | | 9+5x+x=33 | | 22x+440=2x |

Equations solver categories