x^2-9x-2=0

Simple and best practice solution for x^2-9x-2=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^2-9x-2=0 equation:


Simplifying
x2 + -9x + -2 = 0

Reorder the terms:
-2 + -9x + x2 = 0

Solving
-2 + -9x + x2 = 0

Solving for variable 'x'.

Begin completing the square.

Move the constant term to the right:

Add '2' to each side of the equation.
-2 + -9x + 2 + x2 = 0 + 2

Reorder the terms:
-2 + 2 + -9x + x2 = 0 + 2

Combine like terms: -2 + 2 = 0
0 + -9x + x2 = 0 + 2
-9x + x2 = 0 + 2

Combine like terms: 0 + 2 = 2
-9x + x2 = 2

The x term is -9x.  Take half its coefficient (-4.5).
Square it (20.25) and add it to both sides.

Add '20.25' to each side of the equation.
-9x + 20.25 + x2 = 2 + 20.25

Reorder the terms:
20.25 + -9x + x2 = 2 + 20.25

Combine like terms: 2 + 20.25 = 22.25
20.25 + -9x + x2 = 22.25

Factor a perfect square on the left side:
(x + -4.5)(x + -4.5) = 22.25

Calculate the square root of the right side: 4.716990566

Break this problem into two subproblems by setting 
(x + -4.5) equal to 4.716990566 and -4.716990566.

Subproblem 1

x + -4.5 = 4.716990566 Simplifying x + -4.5 = 4.716990566 Reorder the terms: -4.5 + x = 4.716990566 Solving -4.5 + x = 4.716990566 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '4.5' to each side of the equation. -4.5 + 4.5 + x = 4.716990566 + 4.5 Combine like terms: -4.5 + 4.5 = 0.0 0.0 + x = 4.716990566 + 4.5 x = 4.716990566 + 4.5 Combine like terms: 4.716990566 + 4.5 = 9.216990566 x = 9.216990566 Simplifying x = 9.216990566

Subproblem 2

x + -4.5 = -4.716990566 Simplifying x + -4.5 = -4.716990566 Reorder the terms: -4.5 + x = -4.716990566 Solving -4.5 + x = -4.716990566 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '4.5' to each side of the equation. -4.5 + 4.5 + x = -4.716990566 + 4.5 Combine like terms: -4.5 + 4.5 = 0.0 0.0 + x = -4.716990566 + 4.5 x = -4.716990566 + 4.5 Combine like terms: -4.716990566 + 4.5 = -0.216990566 x = -0.216990566 Simplifying x = -0.216990566

Solution

The solution to the problem is based on the solutions from the subproblems. x = {9.216990566, -0.216990566}

See similar equations:

| 2w^4-32= | | 14x+8-5=13x-2 | | x^2-9x-3=0 | | 3s^4-243= | | v^2-v+7= | | 63-12v-3v^2= | | x+2y-4=0 | | -3y+2=-4y+5 | | r^5-10r^4+25r^3= | | 30b^3+145b^2-210b= | | 5+x=-2 | | 6x-18xy= | | 3-2s= | | P-12=-26 | | -4g-5=-17 | | 8x-4+9x=1 | | 7x+21y+21= | | 12=6z-10 | | 25x^2+1=6x | | 7x(x+3)+5=2x(x+4) | | 6t=-38 | | 49x^2-14x+1=0 | | -(7y+2)-(-6y-4)=-6 | | 5(3x-4)=4 | | 16x^2-24x+9=0 | | y=2.2+216 | | y^2+7=6y | | y^2+22=10y | | 4x^2+x-5=0 | | 6(4x-4)=3(8x+7) | | 5+6m-4=8m+4-5m | | 5p+5=4+p |

Equations solver categories