x^2-18x+81=18

Simple and best practice solution for x^2-18x+81=18 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+81=18 equation: 


Simplifying
x2 + -18x + 81 = 18

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

Solving
81 + -18x + x2 = 18

Solving for variable 'x'.

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

Combine like terms: 81 + -18 = 63
63 + -18x + x2 = 18 + -18

Combine like terms: 18 + -18 = 0
63 + -18x + x2 = 0

Begin completing the square.

Move the constant term to the right:

Add '-63' to each side of the equation.
63 + -18x + -63 + x2 = 0 + -63

Reorder the terms:
63 + -63 + -18x + x2 = 0 + -63

Combine like terms: 63 + -63 = 0
0 + -18x + x2 = 0 + -63
-18x + x2 = 0 + -63

Combine like terms: 0 + -63 = -63
-18x + x2 = -63

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 = -63 + 81

Reorder the terms:
81 + -18x + x2 = -63 + 81

Combine like terms: -63 + 81 = 18
81 + -18x + x2 = 18

Factor a perfect square on the left side:
(x + -9)(x + -9) = 18

Calculate the square root of the right side: 4.242640687

Break this problem into two subproblems by setting 
(x + -9) equal to 4.242640687 and -4.242640687.


Subproblem 1
x + -9 = 4.242640687

Simplifying
x + -9 = 4.242640687

Reorder the terms:
-9 + x = 4.242640687

Solving
-9 + x = 4.242640687

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 = 4.242640687 + 9

Combine like terms: -9 + 9 = 0
0 + x = 4.242640687 + 9
x = 4.242640687 + 9

Combine like terms: 4.242640687 + 9 = 13.242640687
x = 13.242640687

Simplifying
x = 13.242640687


Subproblem 2
x + -9 = -4.242640687

Simplifying
x + -9 = -4.242640687

Reorder the terms:
-9 + x = -4.242640687

Solving
-9 + x = -4.242640687

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 = -4.242640687 + 9

Combine like terms: -9 + 9 = 0
0 + x = -4.242640687 + 9
x = -4.242640687 + 9

Combine like terms: -4.242640687 + 9 = 4.757359313
x = 4.757359313

Simplifying
x = 4.757359313


Solution
The solution to the problem is based on the solutions
from the subproblems.
x = {13.242640687, 4.757359313}

See similar equations:

| -2/3z+4=8 | | x+2.5x=140 | | 2/3=a/6+1 | | 50+n-40/4=58 | | x^2+8x+16=-18 | | x+.06x=477 | | Y/2=28 | | 3x+x=14 | | x=48+(x.2) | | X(X-2)+3=5-7X | | E/-25=20 | | a/3-2=-7 | | x^2+4x-52=0 | | 84-3x=12-9x | | x+1.3x=69 | | 5m+1m=3m-9 | | 1600(24-20)+200000=206400 | | Y/-4=-12 | | 4x-5y=75 | | 2y=(4x)-8 | | 6+3x=21-2x | | n+20=m | | 3(A-2)=2(A-7) | | (3/21)(21/21)= | | (x+4)(x-3)+(x+4)(x-5)= | | (4x-z)(4x-7z)= | | 2(x-6)=42/7 | | -2y(y+4)=2 | | n^2+7n-120=0 | | Ln(X^10)-Ln(X^5)=5 | | 3x+15=7x+55 | | 3(a+2)-2(a+1)=6 |

Equations solver categories