9x^2+72x+11=0

Simple and best practice solution for 9x^2+72x+11=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 9x^2+72x+11=0 equation:


Simplifying
9x2 + 72x + 11 = 0

Reorder the terms:
11 + 72x + 9x2 = 0

Solving
11 + 72x + 9x2 = 0

Solving for variable 'x'.

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

Divide each side by '9'.
1.222222222 + 8x + x2 = 0

Move the constant term to the right:

Add '-1.222222222' to each side of the equation.
1.222222222 + 8x + -1.222222222 + x2 = 0 + -1.222222222

Reorder the terms:
1.222222222 + -1.222222222 + 8x + x2 = 0 + -1.222222222

Combine like terms: 1.222222222 + -1.222222222 = 0.000000000
0.000000000 + 8x + x2 = 0 + -1.222222222
8x + x2 = 0 + -1.222222222

Combine like terms: 0 + -1.222222222 = -1.222222222
8x + x2 = -1.222222222

The x term is 8x.  Take half its coefficient (4).
Square it (16) and add it to both sides.

Add '16' to each side of the equation.
8x + 16 + x2 = -1.222222222 + 16

Reorder the terms:
16 + 8x + x2 = -1.222222222 + 16

Combine like terms: -1.222222222 + 16 = 14.777777778
16 + 8x + x2 = 14.777777778

Factor a perfect square on the left side:
(x + 4)(x + 4) = 14.777777778

Calculate the square root of the right side: 3.844187532

Break this problem into two subproblems by setting 
(x + 4) equal to 3.844187532 and -3.844187532.

Subproblem 1

x + 4 = 3.844187532 Simplifying x + 4 = 3.844187532 Reorder the terms: 4 + x = 3.844187532 Solving 4 + x = 3.844187532 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-4' to each side of the equation. 4 + -4 + x = 3.844187532 + -4 Combine like terms: 4 + -4 = 0 0 + x = 3.844187532 + -4 x = 3.844187532 + -4 Combine like terms: 3.844187532 + -4 = -0.155812468 x = -0.155812468 Simplifying x = -0.155812468

Subproblem 2

x + 4 = -3.844187532 Simplifying x + 4 = -3.844187532 Reorder the terms: 4 + x = -3.844187532 Solving 4 + x = -3.844187532 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-4' to each side of the equation. 4 + -4 + x = -3.844187532 + -4 Combine like terms: 4 + -4 = 0 0 + x = -3.844187532 + -4 x = -3.844187532 + -4 Combine like terms: -3.844187532 + -4 = -7.844187532 x = -7.844187532 Simplifying x = -7.844187532

Solution

The solution to the problem is based on the solutions from the subproblems. x = {-0.155812468, -7.844187532}

See similar equations:

| 6-1+10b^2= | | 15x+3=6x+21 | | 10r+9r^2-9r^2+9r= | | 54=3n | | 2-5+5= | | a+3-7=0 | | log(6x)-log(4-x)=log(3) | | 3=6-x | | 6p-1=11 | | -5+6i=x^2 | | 3z+10=16 | | (x^4)-(5x^2)-(9)=0 | | 3x-22=x+20 | | 3x-32=22+x | | 2x^4-6x^3-3x^2+3=0 | | 4x-182=-7x+71 | | 4x+8=3y | | (.12x^2)+(1.56x)+4.81=0 | | 25y^2-30y=-9 | | (.12x^2)+1.56x+4.81=0 | | 9x+3y-4=8 | | x+16.1=38.5 | | 2x+4x=6x-2 | | 5=.25x^3-.5x^2-2.25x+4.5 | | 6a+2b=0 | | -18+6x=6+5x | | x(x+0.0075)=0.00375 | | x(x+0.0075)=0.0003 | | 3(p+1)*(p+1)=81 | | x(x+0.0075)=0.000225 | | x(x+0.0075)=0.00015 | | x(x+0.0075)=0.000075 |

Equations solver categories