3x^2+21x-21=12-2x

Simple and best practice solution for 3x^2+21x-21=12-2x 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 3x^2+21x-21=12-2x equation: 


Simplifying
3x2 + 21x + -21 = 12 + -2x

Reorder the terms:
-21 + 21x + 3x2 = 12 + -2x

Solving
-21 + 21x + 3x2 = 12 + -2x

Solving for variable 'x'.

Reorder the terms:
-21 + -12 + 21x + 2x + 3x2 = 12 + -2x + -12 + 2x

Combine like terms: -21 + -12 = -33
-33 + 21x + 2x + 3x2 = 12 + -2x + -12 + 2x

Combine like terms: 21x + 2x = 23x
-33 + 23x + 3x2 = 12 + -2x + -12 + 2x

Reorder the terms:
-33 + 23x + 3x2 = 12 + -12 + -2x + 2x

Combine like terms: 12 + -12 = 0
-33 + 23x + 3x2 = 0 + -2x + 2x
-33 + 23x + 3x2 = -2x + 2x

Combine like terms: -2x + 2x = 0
-33 + 23x + 3x2 = 0

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

Divide each side by '3'.
-11 + 7.666666667x + x2 = 0

Move the constant term to the right:

Add '11' to each side of the equation.
-11 + 7.666666667x + 11 + x2 = 0 + 11

Reorder the terms:
-11 + 11 + 7.666666667x + x2 = 0 + 11

Combine like terms: -11 + 11 = 0
0 + 7.666666667x + x2 = 0 + 11
7.666666667x + x2 = 0 + 11

Combine like terms: 0 + 11 = 11
7.666666667x + x2 = 11

The x term is 7.666666667x.  Take half its coefficient (3.833333334).
Square it (14.69444445) and add it to both sides.

Add '14.69444445' to each side of the equation.
7.666666667x + 14.69444445 + x2 = 11 + 14.69444445

Reorder the terms:
14.69444445 + 7.666666667x + x2 = 11 + 14.69444445

Combine like terms: 11 + 14.69444445 = 25.69444445
14.69444445 + 7.666666667x + x2 = 25.69444445

Factor a perfect square on the left side:
(x + 3.833333334)(x + 3.833333334) = 25.69444445

Calculate the square root of the right side: 5.068968776

Break this problem into two subproblems by setting 
(x + 3.833333334) equal to 5.068968776 and -5.068968776.


Subproblem 1
x + 3.833333334 = 5.068968776

Simplifying
x + 3.833333334 = 5.068968776

Reorder the terms:
3.833333334 + x = 5.068968776

Solving
3.833333334 + x = 5.068968776

Solving for variable 'x'.

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

Add '-3.833333334' to each side of the equation.
3.833333334 + -3.833333334 + x = 5.068968776 + -3.833333334

Combine like terms: 3.833333334 + -3.833333334 = 0.000000000
0.000000000 + x = 5.068968776 + -3.833333334
x = 5.068968776 + -3.833333334

Combine like terms: 5.068968776 + -3.833333334 = 1.235635442
x = 1.235635442

Simplifying
x = 1.235635442


Subproblem 2
x + 3.833333334 = -5.068968776

Simplifying
x + 3.833333334 = -5.068968776

Reorder the terms:
3.833333334 + x = -5.068968776

Solving
3.833333334 + x = -5.068968776

Solving for variable 'x'.

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

Add '-3.833333334' to each side of the equation.
3.833333334 + -3.833333334 + x = -5.068968776 + -3.833333334

Combine like terms: 3.833333334 + -3.833333334 = 0.000000000
0.000000000 + x = -5.068968776 + -3.833333334
x = -5.068968776 + -3.833333334

Combine like terms: -5.068968776 + -3.833333334 = -8.90230211
x = -8.90230211

Simplifying
x = -8.90230211


Solution
The solution to the problem is based on the solutions
from the subproblems.
x = {1.235635442, -8.90230211}

See similar equations:

| 6x=x+50 | | 3y-12=-6 | | in(2x+1)=3.9 | | 12w=216 | | 9x+7-4(3x-5)= | | 17=2(3p+1)-p | | -2(x+4)-3= | | a+0.81=-6.3 | | 8x+3(2x-1)= | | 6(4z-1)-3(z+6)=5(5z+1) | | 7(x-1)-5= | | 5x+-3(2x+4)= | | 2(3x+1)+4x= | | x+-2x+3=3+-x | | 9t-5(3t-12)=30 | | 5x-3x(2x+4)= | | Y=5x+15 | | 3(x-7)(x+2)= | | 3y(y+5)=42 | | 16-3x=25 | | 32X+81= | | -3x-3=33 | | -m-6m+4=-2m-5 | | 5x+3x=180 | | 4(3x-4)= | | q*q-1=35 | | 5+10x+3-6x= | | 3n+13=3n+13 | | x=-20+54 | | 2(9x-4)= | | -3x+15=9 | | 6s+3=10-5s |

Equations solver categories