3x^2-11x-120=0

Simple and best practice solution for 3x^2-11x-120=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 3x^2-11x-120=0 equation:


Simplifying
3x2 + -11x + -120 = 0

Reorder the terms:
-120 + -11x + 3x2 = 0

Solving
-120 + -11x + 3x2 = 0

Solving for variable 'x'.

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

Divide each side by '3'.
-40 + -3.666666667x + x2 = 0

Move the constant term to the right:

Add '40' to each side of the equation.
-40 + -3.666666667x + 40 + x2 = 0 + 40

Reorder the terms:
-40 + 40 + -3.666666667x + x2 = 0 + 40

Combine like terms: -40 + 40 = 0
0 + -3.666666667x + x2 = 0 + 40
-3.666666667x + x2 = 0 + 40

Combine like terms: 0 + 40 = 40
-3.666666667x + x2 = 40

The x term is -3.666666667x.  Take half its coefficient (-1.833333334).
Square it (3.361111114) and add it to both sides.

Add '3.361111114' to each side of the equation.
-3.666666667x + 3.361111114 + x2 = 40 + 3.361111114

Reorder the terms:
3.361111114 + -3.666666667x + x2 = 40 + 3.361111114

Combine like terms: 40 + 3.361111114 = 43.361111114
3.361111114 + -3.666666667x + x2 = 43.361111114

Factor a perfect square on the left side:
(x + -1.833333334)(x + -1.833333334) = 43.361111114

Calculate the square root of the right side: 6.584915422

Break this problem into two subproblems by setting 
(x + -1.833333334) equal to 6.584915422 and -6.584915422.

Subproblem 1

x + -1.833333334 = 6.584915422 Simplifying x + -1.833333334 = 6.584915422 Reorder the terms: -1.833333334 + x = 6.584915422 Solving -1.833333334 + x = 6.584915422 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '1.833333334' to each side of the equation. -1.833333334 + 1.833333334 + x = 6.584915422 + 1.833333334 Combine like terms: -1.833333334 + 1.833333334 = 0.000000000 0.000000000 + x = 6.584915422 + 1.833333334 x = 6.584915422 + 1.833333334 Combine like terms: 6.584915422 + 1.833333334 = 8.418248756 x = 8.418248756 Simplifying x = 8.418248756

Subproblem 2

x + -1.833333334 = -6.584915422 Simplifying x + -1.833333334 = -6.584915422 Reorder the terms: -1.833333334 + x = -6.584915422 Solving -1.833333334 + x = -6.584915422 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '1.833333334' to each side of the equation. -1.833333334 + 1.833333334 + x = -6.584915422 + 1.833333334 Combine like terms: -1.833333334 + 1.833333334 = 0.000000000 0.000000000 + x = -6.584915422 + 1.833333334 x = -6.584915422 + 1.833333334 Combine like terms: -6.584915422 + 1.833333334 = -4.751582088 x = -4.751582088 Simplifying x = -4.751582088

Solution

The solution to the problem is based on the solutions from the subproblems. x = {8.418248756, -4.751582088}

See similar equations:

| w+2.83=6.92 | | 16r-4r+3r-14r=17 | | (4+x)*x=60 | | 8(x-9)=80 | | g/4=3.4 | | 13-1x=37 | | 4t-t-t-t=12 | | 7x-5=7+4x | | 5(a+3)-4(3-2a)= | | (6x^2-12)+(5x^2-4x)=180 | | 2.9=q/4 | | s+3s+2s+s-4s=12 | | 9(x+6)=65 | | 9.95-0.49r=18.77 | | 4.6=2q | | 8=40m | | 5t+4t-7t=18 | | 4q=13.2 | | 0.49r-9.95=18.77 | | W=4H | | -6=2/3a | | q-18.87=-0.58 | | 4x+650= | | 9b-8b=16 | | (X-4)*(x-4)+5*5=13*13 | | 7x^2+14x+24=6x^2+4x | | t/3=3.37 | | 0=5x^4-16x^3-66x^2+76x+220 | | X(14x-21)=0 | | 9s-2s=7 | | 2(-y-4)+y=3 | | 0.03x-4y=16 |

Equations solver categories