2x^2-21x+5=0

Simple and best practice solution for 2x^2-21x+5=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 2x^2-21x+5=0 equation:


Simplifying
2x2 + -21x + 5 = 0

Reorder the terms:
5 + -21x + 2x2 = 0

Solving
5 + -21x + 2x2 = 0

Solving for variable 'x'.

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

Divide each side by '2'.
2.5 + -10.5x + x2 = 0

Move the constant term to the right:

Add '-2.5' to each side of the equation.
2.5 + -10.5x + -2.5 + x2 = 0 + -2.5

Reorder the terms:
2.5 + -2.5 + -10.5x + x2 = 0 + -2.5

Combine like terms: 2.5 + -2.5 = 0.0
0.0 + -10.5x + x2 = 0 + -2.5
-10.5x + x2 = 0 + -2.5

Combine like terms: 0 + -2.5 = -2.5
-10.5x + x2 = -2.5

The x term is -10.5x.  Take half its coefficient (-5.25).
Square it (27.5625) and add it to both sides.

Add '27.5625' to each side of the equation.
-10.5x + 27.5625 + x2 = -2.5 + 27.5625

Reorder the terms:
27.5625 + -10.5x + x2 = -2.5 + 27.5625

Combine like terms: -2.5 + 27.5625 = 25.0625
27.5625 + -10.5x + x2 = 25.0625

Factor a perfect square on the left side:
(x + -5.25)(x + -5.25) = 25.0625

Calculate the square root of the right side: 5.006246099

Break this problem into two subproblems by setting 
(x + -5.25) equal to 5.006246099 and -5.006246099.

Subproblem 1

x + -5.25 = 5.006246099 Simplifying x + -5.25 = 5.006246099 Reorder the terms: -5.25 + x = 5.006246099 Solving -5.25 + x = 5.006246099 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '5.25' to each side of the equation. -5.25 + 5.25 + x = 5.006246099 + 5.25 Combine like terms: -5.25 + 5.25 = 0.00 0.00 + x = 5.006246099 + 5.25 x = 5.006246099 + 5.25 Combine like terms: 5.006246099 + 5.25 = 10.256246099 x = 10.256246099 Simplifying x = 10.256246099

Subproblem 2

x + -5.25 = -5.006246099 Simplifying x + -5.25 = -5.006246099 Reorder the terms: -5.25 + x = -5.006246099 Solving -5.25 + x = -5.006246099 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '5.25' to each side of the equation. -5.25 + 5.25 + x = -5.006246099 + 5.25 Combine like terms: -5.25 + 5.25 = 0.00 0.00 + x = -5.006246099 + 5.25 x = -5.006246099 + 5.25 Combine like terms: -5.006246099 + 5.25 = 0.243753901 x = 0.243753901 Simplifying x = 0.243753901

Solution

The solution to the problem is based on the solutions from the subproblems. x = {10.256246099, 0.243753901}

See similar equations:

| 22x^2-21x+55=0 | | 22x^2-21x+5=0 | | X^2-7x+100=0 | | n/4+9=14 | | 13+3x+y=113 | | z^4+4iz^2+8=0 | | -4p+q=-6 | | -3k-5(k+8)=-88 | | 2b-1=6 | | x^2-7=-17 | | (6+7i)-(-7+i)= | | 3(6)+7= | | 12n+2=-47 | | 6(-5x+2)-2x=-84 | | 126p^2-49p-7= | | 79=9w-2 | | 30y^2+23y-14=0 | | -8m-6(m-6)=148 | | 2377960+26=3000000 | | -1(-40)= | | 48=6x+3 | | z^4+4z^2+8=0 | | 7r+47=5r+57 | | 200+(n)5= | | 0.06(x+5)=0.03(2x+9)+0.03 | | -x/38 | | 2x-5y=10fory | | -.5(32)*x^2+40x+80=0 | | 0.5(x+200)=0.54x-212 | | 2/3x-20=-6 | | 0.4(4z+5)+11.5=0.5(4z-5) | | -4-3/x=26 |

Equations solver categories