x^2-21x+100=0

Simple and best practice solution for x^2-21x+100=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^2-21x+100=0 equation: 


Simplifying
x2 + -21x + 100 = 0

Reorder the terms:
100 + -21x + x2 = 0

Solving
100 + -21x + x2 = 0

Solving for variable 'x'.

Begin completing the square.

Move the constant term to the right:

Add '-100' to each side of the equation.
100 + -21x + -100 + x2 = 0 + -100

Reorder the terms:
100 + -100 + -21x + x2 = 0 + -100

Combine like terms: 100 + -100 = 0
0 + -21x + x2 = 0 + -100
-21x + x2 = 0 + -100

Combine like terms: 0 + -100 = -100
-21x + x2 = -100

The x term is -21x.  Take half its coefficient (-10.5).
Square it (110.25) and add it to both sides.

Add '110.25' to each side of the equation.
-21x + 110.25 + x2 = -100 + 110.25

Reorder the terms:
110.25 + -21x + x2 = -100 + 110.25

Combine like terms: -100 + 110.25 = 10.25
110.25 + -21x + x2 = 10.25

Factor a perfect square on the left side:
(x + -10.5)(x + -10.5) = 10.25

Calculate the square root of the right side: 3.201562119

Break this problem into two subproblems by setting 
(x + -10.5) equal to 3.201562119 and -3.201562119.


Subproblem 1
x + -10.5 = 3.201562119

Simplifying
x + -10.5 = 3.201562119

Reorder the terms:
-10.5 + x = 3.201562119

Solving
-10.5 + x = 3.201562119

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '10.5' to each side of the equation.
-10.5 + 10.5 + x = 3.201562119 + 10.5

Combine like terms: -10.5 + 10.5 = 0.0
0.0 + x = 3.201562119 + 10.5
x = 3.201562119 + 10.5

Combine like terms: 3.201562119 + 10.5 = 13.701562119
x = 13.701562119

Simplifying
x = 13.701562119


Subproblem 2
x + -10.5 = -3.201562119

Simplifying
x + -10.5 = -3.201562119

Reorder the terms:
-10.5 + x = -3.201562119

Solving
-10.5 + x = -3.201562119

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '10.5' to each side of the equation.
-10.5 + 10.5 + x = -3.201562119 + 10.5

Combine like terms: -10.5 + 10.5 = 0.0
0.0 + x = -3.201562119 + 10.5
x = -3.201562119 + 10.5

Combine like terms: -3.201562119 + 10.5 = 7.298437881
x = 7.298437881

Simplifying
x = 7.298437881


Solution
The solution to the problem is based on the solutions
from the subproblems.
x = {13.701562119, 7.298437881}

See similar equations:

| 6(x*x*x)-(x*x)-4(x)+1=0 | | 3w-8=w/2+2 | | y=x^2+8x-13 | | (11x^2)/3-9x-5=0 | | 29.6+36.12= | | 4x-6=2(x-60) | | -x/2 | | 6x-17x+13=20x^2-32 | | -3=12x^2+13x | | M-15.75=23/4 | | 1/2x=13 | | 5ln(9x)=13 | | x+2/3+x-3/4 | | 7s-4=52 | | 28x^2-81x+45=0 | | -1/2+y=3/4 | | 16-16+x=-15 | | 7x/10+2/1=16/1 | | z^2-7z-44=0 | | -(x+4)= | | Log(x-5)+log(x-2)=1 | | 3(-7x)= | | 6-2=-11 | | -3825=2t+-5t | | 8-3lnx=12 | | (-4x)(-6)= | | 4/(8-5i) | | (-x)7y= | | 17=92+g | | 4(x-4)=(2x+5)+(1-x) | | -12x+(-10x)= | | -3x(-4y)= |

Equations solver categories