x+6+4x^2=81

Simple and best practice solution for x+6+4x^2=81 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+6+4x^2=81 equation:


Simplifying
x + 6 + 4x2 = 81

Reorder the terms:
6 + x + 4x2 = 81

Solving
6 + x + 4x2 = 81

Solving for variable 'x'.

Reorder the terms:
6 + -81 + x + 4x2 = 81 + -81

Combine like terms: 6 + -81 = -75
-75 + x + 4x2 = 81 + -81

Combine like terms: 81 + -81 = 0
-75 + x + 4x2 = 0

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

Divide each side by '4'.
-18.75 + 0.25x + x2 = 0

Move the constant term to the right:

Add '18.75' to each side of the equation.
-18.75 + 0.25x + 18.75 + x2 = 0 + 18.75

Reorder the terms:
-18.75 + 18.75 + 0.25x + x2 = 0 + 18.75

Combine like terms: -18.75 + 18.75 = 0.00
0.00 + 0.25x + x2 = 0 + 18.75
0.25x + x2 = 0 + 18.75

Combine like terms: 0 + 18.75 = 18.75
0.25x + x2 = 18.75

The x term is x.  Take half its coefficient (0.5).
Square it (0.25) and add it to both sides.

Add '0.25' to each side of the equation.
0.25x + 0.25 + x2 = 18.75 + 0.25

Reorder the terms:
0.25 + 0.25x + x2 = 18.75 + 0.25

Combine like terms: 18.75 + 0.25 = 19
0.25 + 0.25x + x2 = 19

Factor a perfect square on the left side:
(x + 0.5)(x + 0.5) = 19

Calculate the square root of the right side: 4.358898944

Break this problem into two subproblems by setting 
(x + 0.5) equal to 4.358898944 and -4.358898944.

Subproblem 1

x + 0.5 = 4.358898944 Simplifying x + 0.5 = 4.358898944 Reorder the terms: 0.5 + x = 4.358898944 Solving 0.5 + x = 4.358898944 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-0.5' to each side of the equation. 0.5 + -0.5 + x = 4.358898944 + -0.5 Combine like terms: 0.5 + -0.5 = 0.0 0.0 + x = 4.358898944 + -0.5 x = 4.358898944 + -0.5 Combine like terms: 4.358898944 + -0.5 = 3.858898944 x = 3.858898944 Simplifying x = 3.858898944

Subproblem 2

x + 0.5 = -4.358898944 Simplifying x + 0.5 = -4.358898944 Reorder the terms: 0.5 + x = -4.358898944 Solving 0.5 + x = -4.358898944 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-0.5' to each side of the equation. 0.5 + -0.5 + x = -4.358898944 + -0.5 Combine like terms: 0.5 + -0.5 = 0.0 0.0 + x = -4.358898944 + -0.5 x = -4.358898944 + -0.5 Combine like terms: -4.358898944 + -0.5 = -4.858898944 x = -4.858898944 Simplifying x = -4.858898944

Solution

The solution to the problem is based on the solutions from the subproblems. x = {3.858898944, -4.858898944}

See similar equations:

| 5/6x-17=8 | | 4h+8g=30 | | 77/10-q=13/10 | | (x)2+15=9 | | 4x^2+x-75=0 | | -4(3x+5)= | | 0.19-1.13x=12.39 | | 4y-10+y+38=7y+30-4y | | 14x^2y^3=42x^3y^2 | | 2/3m+1/5m=26 | | 7(x+3)=11x-5 | | 6y+4y+y=18 | | 4(-5-6X)=172 | | 4(5x-3)=48 | | 2(4x-3)=4+2x | | -4x-20=-100 | | 8x^2+3x+18=0 | | =10m+45 | | 0.4x-1.2=1.5x+0.8 | | 7/10-m=1/5 | | 2n^3-30n^3+100n=0 | | 1/5x+1/4x=18 | | 9y=-6y+60 | | 4y-8=2y+2 | | 6(2e+4)=-3c-21 | | 4x+5x=360 | | (1)3/5 | | -5x-23=-103 | | -3(a+4)=-9a-2 | | 7n*8+3+3=-1 | | .6667x-4=-.75x+.5 | | 14y-7=12y-9 |

Equations solver categories