x*x+11x-18=0

Simple and best practice solution for x*x+11x-18=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*x+11x-18=0 equation:


Simplifying
x * x + 11x + -18 = 0

Multiply x * x
x2 + 11x + -18 = 0

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

Solving
-18 + 11x + x2 = 0

Solving for variable 'x'.

Begin completing the square.

Move the constant term to the right:

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

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

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

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

The x term is 11x.  Take half its coefficient (5.5).
Square it (30.25) and add it to both sides.

Add '30.25' to each side of the equation.
11x + 30.25 + x2 = 18 + 30.25

Reorder the terms:
30.25 + 11x + x2 = 18 + 30.25

Combine like terms: 18 + 30.25 = 48.25
30.25 + 11x + x2 = 48.25

Factor a perfect square on the left side:
(x + 5.5)(x + 5.5) = 48.25

Calculate the square root of the right side: 6.946221995

Break this problem into two subproblems by setting 
(x + 5.5) equal to 6.946221995 and -6.946221995.

Subproblem 1

x + 5.5 = 6.946221995 Simplifying x + 5.5 = 6.946221995 Reorder the terms: 5.5 + x = 6.946221995 Solving 5.5 + x = 6.946221995 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-5.5' to each side of the equation. 5.5 + -5.5 + x = 6.946221995 + -5.5 Combine like terms: 5.5 + -5.5 = 0.0 0.0 + x = 6.946221995 + -5.5 x = 6.946221995 + -5.5 Combine like terms: 6.946221995 + -5.5 = 1.446221995 x = 1.446221995 Simplifying x = 1.446221995

Subproblem 2

x + 5.5 = -6.946221995 Simplifying x + 5.5 = -6.946221995 Reorder the terms: 5.5 + x = -6.946221995 Solving 5.5 + x = -6.946221995 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-5.5' to each side of the equation. 5.5 + -5.5 + x = -6.946221995 + -5.5 Combine like terms: 5.5 + -5.5 = 0.0 0.0 + x = -6.946221995 + -5.5 x = -6.946221995 + -5.5 Combine like terms: -6.946221995 + -5.5 = -12.446221995 x = -12.446221995 Simplifying x = -12.446221995

Solution

The solution to the problem is based on the solutions from the subproblems. x = {1.446221995, -12.446221995}

See similar equations:

| 3(x+2)-4(2x-5)= | | cos(2x-(pi/4))=(sqrt(2)/2) | | 4a+2b+3c=57 | | 5y^2+16y+0=0 | | 5x+25x=15x+29 | | 4x+6y=27000 | | 4w-28= | | 3x-7x+x+3x-5x+5=125 | | 1.99/50/50 | | x=x-3/x-1 | | f(x)=x-3/x-1 | | 28(-11-10x)-3x=-15 | | 3x+15=9x+30 | | 4(t+1)=3(t-2) | | 12x-11=-2(1-4x) | | (2+x)(4-3x)= | | X^4+16x^2-36=0 | | 16x^2+x^4=36 | | 3x+2y=1px+2y=5 | | 6x+31=14x+33 | | 19-9(-7)+6= | | 57-3b=93-7b | | 4w+29=65 | | (6-4)/(5-8)= | | 8h+10=10 | | 3x+4x-x+300=105-10x | | ((81a^6)/(144b^12))^(1/2) | | 12x^2+4x+10=0 | | 15e-7=7+2e | | 5x^3+-24x^2+36x-16=0 | | 2k+34=80-7k | | Sen(x+60)=cos(10+x) |

Equations solver categories