3x+8x=x^2-3x-12

Simple and best practice solution for 3x+8x=x^2-3x-12 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+8x=x^2-3x-12 equation:


Simplifying
3x + 8x = x2 + -3x + -12

Combine like terms: 3x + 8x = 11x
11x = x2 + -3x + -12

Reorder the terms:
11x = -12 + -3x + x2

Solving
11x = -12 + -3x + x2

Solving for variable 'x'.

Reorder the terms:
12 + 11x + 3x + -1x2 = -12 + -3x + x2 + 12 + 3x + -1x2

Combine like terms: 11x + 3x = 14x
12 + 14x + -1x2 = -12 + -3x + x2 + 12 + 3x + -1x2

Reorder the terms:
12 + 14x + -1x2 = -12 + 12 + -3x + 3x + x2 + -1x2

Combine like terms: -12 + 12 = 0
12 + 14x + -1x2 = 0 + -3x + 3x + x2 + -1x2
12 + 14x + -1x2 = -3x + 3x + x2 + -1x2

Combine like terms: -3x + 3x = 0
12 + 14x + -1x2 = 0 + x2 + -1x2
12 + 14x + -1x2 = x2 + -1x2

Combine like terms: x2 + -1x2 = 0
12 + 14x + -1x2 = 0

Begin completing the square.  Divide all terms by
-1 the coefficient of the squared term: 

Divide each side by '-1'.
-12 + -14x + x2 = 0

Move the constant term to the right:

Add '12' to each side of the equation.
-12 + -14x + 12 + x2 = 0 + 12

Reorder the terms:
-12 + 12 + -14x + x2 = 0 + 12

Combine like terms: -12 + 12 = 0
0 + -14x + x2 = 0 + 12
-14x + x2 = 0 + 12

Combine like terms: 0 + 12 = 12
-14x + x2 = 12

The x term is -14x.  Take half its coefficient (-7).
Square it (49) and add it to both sides.

Add '49' to each side of the equation.
-14x + 49 + x2 = 12 + 49

Reorder the terms:
49 + -14x + x2 = 12 + 49

Combine like terms: 12 + 49 = 61
49 + -14x + x2 = 61

Factor a perfect square on the left side:
(x + -7)(x + -7) = 61

Calculate the square root of the right side: 7.810249676

Break this problem into two subproblems by setting 
(x + -7) equal to 7.810249676 and -7.810249676.

Subproblem 1

x + -7 = 7.810249676 Simplifying x + -7 = 7.810249676 Reorder the terms: -7 + x = 7.810249676 Solving -7 + x = 7.810249676 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '7' to each side of the equation. -7 + 7 + x = 7.810249676 + 7 Combine like terms: -7 + 7 = 0 0 + x = 7.810249676 + 7 x = 7.810249676 + 7 Combine like terms: 7.810249676 + 7 = 14.810249676 x = 14.810249676 Simplifying x = 14.810249676

Subproblem 2

x + -7 = -7.810249676 Simplifying x + -7 = -7.810249676 Reorder the terms: -7 + x = -7.810249676 Solving -7 + x = -7.810249676 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '7' to each side of the equation. -7 + 7 + x = -7.810249676 + 7 Combine like terms: -7 + 7 = 0 0 + x = -7.810249676 + 7 x = -7.810249676 + 7 Combine like terms: -7.810249676 + 7 = -0.810249676 x = -0.810249676 Simplifying x = -0.810249676

Solution

The solution to the problem is based on the solutions from the subproblems. x = {14.810249676, -0.810249676}

See similar equations:

| (X-(2/7))(x-(1/3))=0 | | -1/2-1 | | 2x-7y=31 | | -3.2+9x=0 | | 5x+-2y=48 | | 2r=-12 | | 50+8n= | | -14u+6u+12u+-3=9 | | -14y+13y+-16=4 | | s-10=-7 | | 4x*2=2048x | | 4+2y=-8x | | -5n^2=-320 | | 5x^2-3x^3+6x=8 | | -4(z+9)=7-3z | | 5m-21= | | 100=800(.02)(t) | | 7+18=74 | | D=3h+2 | | d=-0.5+7 | | 0=13.303x^2-241.442x+1659.567 | | 3m^2-5m-7=0 | | 6v^2=9 | | 2x+5=27x-4 | | 2x+5x^2=2x | | 4.24x+25.44=50.88 | | A=2x+12x+16 | | =(3s-15t)-(-28s+7t) | | Y=60000+.2x | | -2(-3+5)+6=4(x+2) | | 8y+x=12 | | 126=6r-8(6+8r) |

Equations solver categories