x^2+18x+11=0

Simple and best practice solution for x^2+18x+11=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+18x+11=0 equation:


Simplifying
x2 + 18x + 11 = 0

Reorder the terms:
11 + 18x + x2 = 0

Solving
11 + 18x + x2 = 0

Solving for variable 'x'.

Begin completing the square.

Move the constant term to the right:

Add '-11' to each side of the equation.
11 + 18x + -11 + x2 = 0 + -11

Reorder the terms:
11 + -11 + 18x + x2 = 0 + -11

Combine like terms: 11 + -11 = 0
0 + 18x + x2 = 0 + -11
18x + x2 = 0 + -11

Combine like terms: 0 + -11 = -11
18x + x2 = -11

The x term is 18x.  Take half its coefficient (9).
Square it (81) and add it to both sides.

Add '81' to each side of the equation.
18x + 81 + x2 = -11 + 81

Reorder the terms:
81 + 18x + x2 = -11 + 81

Combine like terms: -11 + 81 = 70
81 + 18x + x2 = 70

Factor a perfect square on the left side:
(x + 9)(x + 9) = 70

Calculate the square root of the right side: 8.366600265

Break this problem into two subproblems by setting 
(x + 9) equal to 8.366600265 and -8.366600265.

Subproblem 1

x + 9 = 8.366600265 Simplifying x + 9 = 8.366600265 Reorder the terms: 9 + x = 8.366600265 Solving 9 + x = 8.366600265 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-9' to each side of the equation. 9 + -9 + x = 8.366600265 + -9 Combine like terms: 9 + -9 = 0 0 + x = 8.366600265 + -9 x = 8.366600265 + -9 Combine like terms: 8.366600265 + -9 = -0.633399735 x = -0.633399735 Simplifying x = -0.633399735

Subproblem 2

x + 9 = -8.366600265 Simplifying x + 9 = -8.366600265 Reorder the terms: 9 + x = -8.366600265 Solving 9 + x = -8.366600265 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-9' to each side of the equation. 9 + -9 + x = -8.366600265 + -9 Combine like terms: 9 + -9 = 0 0 + x = -8.366600265 + -9 x = -8.366600265 + -9 Combine like terms: -8.366600265 + -9 = -17.366600265 x = -17.366600265 Simplifying x = -17.366600265

Solution

The solution to the problem is based on the solutions from the subproblems. x = {-0.633399735, -17.366600265}

See similar equations:

| 7x+9y+4x-6y= | | 4(x-2)+4=8 | | 28=x+5x+4 | | 8x-32-10=22x-196 | | 12s+7rt=15s | | 12s+7rt=15 | | m+3(m-34)=16 | | 15-7n=65 | | X-56=124-5X | | x/-8=-10-(-11) | | 3(5t-3)-t=3(3t-2) | | 6/7y=3 | | 12/6f=-18 | | 3/n+n/12-6=5+2n-18 | | 2x-5x-x=19-5 | | 27.12/0.06 | | 5u^2-8u-13=0 | | n+4-2n=10 | | x+550=35x | | 4n/5-7/13=69/65 | | 2x+24+3x=-10+94 | | y^6-8y^3=0 | | 560x=35x | | 3x+1=57-5x | | -5/6=-5/4+s | | 5(y-2)/3=-3y | | 18*18= | | x/5+x/8=13/40 | | -90=-9x | | 7a+2=5a+12 | | d-2.7=-2+2d | | -10x-60+460=26+14 |

Equations solver categories