x^2+12x+9=0

Simple and best practice solution for x^2+12x+9=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+12x+9=0 equation:


Simplifying
x2 + 12x + 9 = 0

Reorder the terms:
9 + 12x + x2 = 0

Solving
9 + 12x + x2 = 0

Solving for variable 'x'.

Begin completing the square.

Move the constant term to the right:

Add '-9' to each side of the equation.
9 + 12x + -9 + x2 = 0 + -9

Reorder the terms:
9 + -9 + 12x + x2 = 0 + -9

Combine like terms: 9 + -9 = 0
0 + 12x + x2 = 0 + -9
12x + x2 = 0 + -9

Combine like terms: 0 + -9 = -9
12x + x2 = -9

The x term is 12x.  Take half its coefficient (6).
Square it (36) and add it to both sides.

Add '36' to each side of the equation.
12x + 36 + x2 = -9 + 36

Reorder the terms:
36 + 12x + x2 = -9 + 36

Combine like terms: -9 + 36 = 27
36 + 12x + x2 = 27

Factor a perfect square on the left side:
(x + 6)(x + 6) = 27

Calculate the square root of the right side: 5.196152423

Break this problem into two subproblems by setting 
(x + 6) equal to 5.196152423 and -5.196152423.

Subproblem 1

x + 6 = 5.196152423 Simplifying x + 6 = 5.196152423 Reorder the terms: 6 + x = 5.196152423 Solving 6 + x = 5.196152423 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-6' to each side of the equation. 6 + -6 + x = 5.196152423 + -6 Combine like terms: 6 + -6 = 0 0 + x = 5.196152423 + -6 x = 5.196152423 + -6 Combine like terms: 5.196152423 + -6 = -0.803847577 x = -0.803847577 Simplifying x = -0.803847577

Subproblem 2

x + 6 = -5.196152423 Simplifying x + 6 = -5.196152423 Reorder the terms: 6 + x = -5.196152423 Solving 6 + x = -5.196152423 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-6' to each side of the equation. 6 + -6 + x = -5.196152423 + -6 Combine like terms: 6 + -6 = 0 0 + x = -5.196152423 + -6 x = -5.196152423 + -6 Combine like terms: -5.196152423 + -6 = -11.196152423 x = -11.196152423 Simplifying x = -11.196152423

Solution

The solution to the problem is based on the solutions from the subproblems. x = {-0.803847577, -11.196152423}

See similar equations:

| 18.6-3.5y=1.16666 | | 6x-x^2=5 | | 132=8r+36 | | 3.9x-58=2.7x+2 | | X^2+3=56 | | 4w^2-88=0 | | 3a/8-a/12+7/2=7 | | z/3-3z/4=-1/3 | | t^2-6t=-6 | | 2r/5-4/5=2/5 | | 2(x)20=900 | | 2t/3+1/3=-1/3 | | 16x^2-34x-15=0 | | x(46)+(-900)46= | | a^2+8a-3=0 | | 10+x=4x-5 | | 5c^3+40c^2-45c=0 | | 95x+65x=35x+25x | | 2+4x=6x-8 | | 6+7x=2x+11 | | 6x+9=54+x | | 6x+8=3x+11 | | 7x+4=2x-6 | | 3x^4+10x^2+7=0 | | 2m^2+8m+5=0 | | A=3-4*(5-2) | | -x+5=2x-7 | | v+4=-3v-16 | | 6(z+3)+3z=-36 | | 162-45k+3m^2=0 | | 5-6z=9-6z | | 50+20t+2t^2=0 |

Equations solver categories