0=x^2-11x-90

Simple and best practice solution for 0=x^2-11x-90 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 0=x^2-11x-90 equation:


Simplifying
0 = x2 + -11x + -90

Reorder the terms:
0 = -90 + -11x + x2

Solving
0 = -90 + -11x + x2

Solving for variable 'x'.

Combine like terms: 0 + 90 = 90
90 + 11x + -1x2 = -90 + -11x + x2 + 90 + 11x + -1x2

Reorder the terms:
90 + 11x + -1x2 = -90 + 90 + -11x + 11x + x2 + -1x2

Combine like terms: -90 + 90 = 0
90 + 11x + -1x2 = 0 + -11x + 11x + x2 + -1x2
90 + 11x + -1x2 = -11x + 11x + x2 + -1x2

Combine like terms: -11x + 11x = 0
90 + 11x + -1x2 = 0 + x2 + -1x2
90 + 11x + -1x2 = x2 + -1x2

Combine like terms: x2 + -1x2 = 0
90 + 11x + -1x2 = 0

Begin completing the square.  Divide all terms by
-1 the coefficient of the squared term: 

Divide each side by '-1'.
-90 + -11x + x2 = 0

Move the constant term to the right:

Add '90' to each side of the equation.
-90 + -11x + 90 + x2 = 0 + 90

Reorder the terms:
-90 + 90 + -11x + x2 = 0 + 90

Combine like terms: -90 + 90 = 0
0 + -11x + x2 = 0 + 90
-11x + x2 = 0 + 90

Combine like terms: 0 + 90 = 90
-11x + x2 = 90

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 = 90 + 30.25

Reorder the terms:
30.25 + -11x + x2 = 90 + 30.25

Combine like terms: 90 + 30.25 = 120.25
30.25 + -11x + x2 = 120.25

Factor a perfect square on the left side:
(x + -5.5)(x + -5.5) = 120.25

Calculate the square root of the right side: 10.9658561

Break this problem into two subproblems by setting 
(x + -5.5) equal to 10.9658561 and -10.9658561.

Subproblem 1

x + -5.5 = 10.9658561 Simplifying x + -5.5 = 10.9658561 Reorder the terms: -5.5 + x = 10.9658561 Solving -5.5 + x = 10.9658561 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 = 10.9658561 + 5.5 Combine like terms: -5.5 + 5.5 = 0.0 0.0 + x = 10.9658561 + 5.5 x = 10.9658561 + 5.5 Combine like terms: 10.9658561 + 5.5 = 16.4658561 x = 16.4658561 Simplifying x = 16.4658561

Subproblem 2

x + -5.5 = -10.9658561 Simplifying x + -5.5 = -10.9658561 Reorder the terms: -5.5 + x = -10.9658561 Solving -5.5 + x = -10.9658561 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 = -10.9658561 + 5.5 Combine like terms: -5.5 + 5.5 = 0.0 0.0 + x = -10.9658561 + 5.5 x = -10.9658561 + 5.5 Combine like terms: -10.9658561 + 5.5 = -5.4658561 x = -5.4658561 Simplifying x = -5.4658561

Solution

The solution to the problem is based on the solutions from the subproblems. x = {16.4658561, -5.4658561}

See similar equations:

| 4xy(2x^4-xy+3)= | | -8x+y+1=0 | | 3w-21=-6(w-7) | | -8+y+1=0 | | -9y=1.8 | | 100x^2=7 | | -4y=5x-3 | | -2(X-4)+6=4 | | 8x^5y-4xy^2+12xy= | | 6+y+1=0 | | 0+y+1=0 | | -6X^2+4X-1=0 | | y+1(0)=0 | | 2(x+2)=3(x+9) | | 7x-3=6+x | | 4x+7-3x-8=17 | | 62+7(x+1)=90 | | 3a=6b+9 | | 2x=3x-12-5x | | a-2b=3 | | Y-25+y=180 | | -2X^2-3X-5=0 | | 3+3d-5=3d-2 | | -5h=h+-6 | | 7.1q+2.9=8 | | 3(x+4)+2(x-3)=-24 | | 4x-7x=21 | | 3(t+1)=18 | | X^3-5x^2-x=-5 | | 10n-4n= | | -5-11z=9z+7 | | 61.1=4.8h+9.5 |

Equations solver categories