x^2-4x-80=0

Simple and best practice solution for x^2-4x-80=0 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 x^2-4x-80=0 equation:


Simplifying
x2 + -4x + -80 = 0

Reorder the terms:
-80 + -4x + x2 = 0

Solving
-80 + -4x + x2 = 0

Solving for variable 'x'.

Begin completing the square.

Move the constant term to the right:

Add '80' to each side of the equation.
-80 + -4x + 80 + x2 = 0 + 80

Reorder the terms:
-80 + 80 + -4x + x2 = 0 + 80

Combine like terms: -80 + 80 = 0
0 + -4x + x2 = 0 + 80
-4x + x2 = 0 + 80

Combine like terms: 0 + 80 = 80
-4x + x2 = 80

The x term is -4x.  Take half its coefficient (-2).
Square it (4) and add it to both sides.

Add '4' to each side of the equation.
-4x + 4 + x2 = 80 + 4

Reorder the terms:
4 + -4x + x2 = 80 + 4

Combine like terms: 80 + 4 = 84
4 + -4x + x2 = 84

Factor a perfect square on the left side:
(x + -2)(x + -2) = 84

Calculate the square root of the right side: 9.16515139

Break this problem into two subproblems by setting 
(x + -2) equal to 9.16515139 and -9.16515139.

Subproblem 1

x + -2 = 9.16515139 Simplifying x + -2 = 9.16515139 Reorder the terms: -2 + x = 9.16515139 Solving -2 + x = 9.16515139 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '2' to each side of the equation. -2 + 2 + x = 9.16515139 + 2 Combine like terms: -2 + 2 = 0 0 + x = 9.16515139 + 2 x = 9.16515139 + 2 Combine like terms: 9.16515139 + 2 = 11.16515139 x = 11.16515139 Simplifying x = 11.16515139

Subproblem 2

x + -2 = -9.16515139 Simplifying x + -2 = -9.16515139 Reorder the terms: -2 + x = -9.16515139 Solving -2 + x = -9.16515139 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '2' to each side of the equation. -2 + 2 + x = -9.16515139 + 2 Combine like terms: -2 + 2 = 0 0 + x = -9.16515139 + 2 x = -9.16515139 + 2 Combine like terms: -9.16515139 + 2 = -7.16515139 x = -7.16515139 Simplifying x = -7.16515139

Solution

The solution to the problem is based on the solutions from the subproblems. x = {11.16515139, -7.16515139}

See similar equations:

| 3x-26=12 | | 2.2/5=x/4 | | x/2-3/4=(5/8)x+9/4 | | 4.8/7=x/4 | | 2/3=x/4 | | 2.4/5=x/4 | | B(14+b)=0 | | t=25 | | 5.8/7=x/4 | | (4w+3v)(4w-3v)= | | (2x+3)(x-2)=2x | | 5n+3x=n | | 4(x-7)+2=-5(x-2) | | x+3y=n-1 | | 5n+3x= | | 3x-6x=9x | | 16-64=0 | | f(x)=9+1 | | f(x)=-3+1 | | 6(-70%x+6)=5*8-2x | | (3/2)x=15 | | f(x)=-2(3)-5 | | (3x-6)(2x-2)=0 | | 1/4+2x=1/5x+1 | | 75=5+3x | | (x+2)*(x+1)+(x+3)*(x+1)=2x^2+12 | | .3x+1=13 | | 8x-2x+62=-8x+40 | | .5t+4=1 | | 3x+6(x+15)=162 | | 7x+3(2x+4)=116 | | 12.79+.11h=13.54-.07h |

Equations solver categories