(x*x)+3x-128=0

Simple and best practice solution for (x*x)+3x-128=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 (x*x)+3x-128=0 equation:


Simplifying
(x * x) + 3x + -128 = 0

Multiply x * x
(x2) + 3x + -128 = 0
x2 + 3x + -128 = 0

Reorder the terms:
-128 + 3x + x2 = 0

Solving
-128 + 3x + x2 = 0

Solving for variable 'x'.

Begin completing the square.

Move the constant term to the right:

Add '128' to each side of the equation.
-128 + 3x + 128 + x2 = 0 + 128

Reorder the terms:
-128 + 128 + 3x + x2 = 0 + 128

Combine like terms: -128 + 128 = 0
0 + 3x + x2 = 0 + 128
3x + x2 = 0 + 128

Combine like terms: 0 + 128 = 128
3x + x2 = 128

The x term is 3x.  Take half its coefficient (1.5).
Square it (2.25) and add it to both sides.

Add '2.25' to each side of the equation.
3x + 2.25 + x2 = 128 + 2.25

Reorder the terms:
2.25 + 3x + x2 = 128 + 2.25

Combine like terms: 128 + 2.25 = 130.25
2.25 + 3x + x2 = 130.25

Factor a perfect square on the left side:
(x + 1.5)(x + 1.5) = 130.25

Calculate the square root of the right side: 11.412712211

Break this problem into two subproblems by setting 
(x + 1.5) equal to 11.412712211 and -11.412712211.

Subproblem 1

x + 1.5 = 11.412712211 Simplifying x + 1.5 = 11.412712211 Reorder the terms: 1.5 + x = 11.412712211 Solving 1.5 + x = 11.412712211 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-1.5' to each side of the equation. 1.5 + -1.5 + x = 11.412712211 + -1.5 Combine like terms: 1.5 + -1.5 = 0.0 0.0 + x = 11.412712211 + -1.5 x = 11.412712211 + -1.5 Combine like terms: 11.412712211 + -1.5 = 9.912712211 x = 9.912712211 Simplifying x = 9.912712211

Subproblem 2

x + 1.5 = -11.412712211 Simplifying x + 1.5 = -11.412712211 Reorder the terms: 1.5 + x = -11.412712211 Solving 1.5 + x = -11.412712211 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-1.5' to each side of the equation. 1.5 + -1.5 + x = -11.412712211 + -1.5 Combine like terms: 1.5 + -1.5 = 0.0 0.0 + x = -11.412712211 + -1.5 x = -11.412712211 + -1.5 Combine like terms: -11.412712211 + -1.5 = -12.912712211 x = -12.912712211 Simplifying x = -12.912712211

Solution

The solution to the problem is based on the solutions from the subproblems. x = {9.912712211, -12.912712211}

See similar equations:

| (x/2)-18=53 | | 3/8/-5/18 | | 12*y-10=2y | | abs(x)+abs(1-x)+2abs(y)=1 | | 6.5m+12.4=10.75m-8.85 | | 3x/4=x-8 | | 4x-10=20-6x | | 5+3(10x-2)=89 | | 5s+6t=51 | | 10x-650+50=250 | | 2s+3t=24 | | (2x-5)(3x^2-4)= | | 3-1=14 | | 2x+29=90 | | 2y+3x=15.5 | | ln12x^2/3y | | X+29+x=90 | | 13p+6q=50 | | 2v^2+10=74 | | 5(3x+2)=60 | | sin(4x)cos(6x)-cos(4x)sin(6x)=-0.35 | | 10(2-x)=15(x-1)+5 | | 2(-4x-6)=-100 | | 2(-5a-8)+4=50 | | s/15.42=63 | | 35=x+(x+4)+(x+7) | | 1800=xa | | 5t^2-1=4t^4 | | 5(x-3)-4=2(x-1)+7 | | 1800=(a+10)(x-30) | | 10x^2-24x=16 | | 3(-6x+4)=-204 |

Equations solver categories