3x(7x-2)=20

Simple and best practice solution for 3x(7x-2)=20 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(7x-2)=20 equation:


Simplifying
3x(7x + -2) = 20

Reorder the terms:
3x(-2 + 7x) = 20
(-2 * 3x + 7x * 3x) = 20
(-6x + 21x2) = 20

Solving
-6x + 21x2 = 20

Solving for variable 'x'.

Reorder the terms:
-20 + -6x + 21x2 = 20 + -20

Combine like terms: 20 + -20 = 0
-20 + -6x + 21x2 = 0

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

Divide each side by '21'.
-0.9523809524 + -0.2857142857x + x2 = 0

Move the constant term to the right:

Add '0.9523809524' to each side of the equation.
-0.9523809524 + -0.2857142857x + 0.9523809524 + x2 = 0 + 0.9523809524

Reorder the terms:
-0.9523809524 + 0.9523809524 + -0.2857142857x + x2 = 0 + 0.9523809524

Combine like terms: -0.9523809524 + 0.9523809524 = 0.0000000000
0.0000000000 + -0.2857142857x + x2 = 0 + 0.9523809524
-0.2857142857x + x2 = 0 + 0.9523809524

Combine like terms: 0 + 0.9523809524 = 0.9523809524
-0.2857142857x + x2 = 0.9523809524

The x term is -0.2857142857x.  Take half its coefficient (-0.1428571429).
Square it (0.02040816328) and add it to both sides.

Add '0.02040816328' to each side of the equation.
-0.2857142857x + 0.02040816328 + x2 = 0.9523809524 + 0.02040816328

Reorder the terms:
0.02040816328 + -0.2857142857x + x2 = 0.9523809524 + 0.02040816328

Combine like terms: 0.9523809524 + 0.02040816328 = 0.97278911568
0.02040816328 + -0.2857142857x + x2 = 0.97278911568

Factor a perfect square on the left side:
(x + -0.1428571429)(x + -0.1428571429) = 0.97278911568

Calculate the square root of the right side: 0.986300723

Break this problem into two subproblems by setting 
(x + -0.1428571429) equal to 0.986300723 and -0.986300723.

Subproblem 1

x + -0.1428571429 = 0.986300723 Simplifying x + -0.1428571429 = 0.986300723 Reorder the terms: -0.1428571429 + x = 0.986300723 Solving -0.1428571429 + x = 0.986300723 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '0.1428571429' to each side of the equation. -0.1428571429 + 0.1428571429 + x = 0.986300723 + 0.1428571429 Combine like terms: -0.1428571429 + 0.1428571429 = 0.0000000000 0.0000000000 + x = 0.986300723 + 0.1428571429 x = 0.986300723 + 0.1428571429 Combine like terms: 0.986300723 + 0.1428571429 = 1.1291578659 x = 1.1291578659 Simplifying x = 1.1291578659

Subproblem 2

x + -0.1428571429 = -0.986300723 Simplifying x + -0.1428571429 = -0.986300723 Reorder the terms: -0.1428571429 + x = -0.986300723 Solving -0.1428571429 + x = -0.986300723 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '0.1428571429' to each side of the equation. -0.1428571429 + 0.1428571429 + x = -0.986300723 + 0.1428571429 Combine like terms: -0.1428571429 + 0.1428571429 = 0.0000000000 0.0000000000 + x = -0.986300723 + 0.1428571429 x = -0.986300723 + 0.1428571429 Combine like terms: -0.986300723 + 0.1428571429 = -0.8434435801 x = -0.8434435801 Simplifying x = -0.8434435801

Solution

The solution to the problem is based on the solutions from the subproblems. x = {1.1291578659, -0.8434435801}

See similar equations:

| H(q)=3q-2(q^2-4q) | | 78-7x=29x+22 | | 2g-7=12 | | 9-9x=49-16x | | -100-9x=49-16x | | -5-3x=4x+12 | | 69-3x=10x+18 | | 7+4x=31+x | | 273-3x=42x+18 | | 14-10x=94-38x | | -17-9x=10x+21 | | 8x-27=37 | | 8-5x=14-7x | | 152-5x=4x+17 | | 3m-8=-13 | | 2x^8=10 | | 4x+22=11x-41 | | 41-2x=7x+17 | | 102-4x=4x+14 | | 5-9x=41-30x | | -65-2x=7-10x | | -72-9x=9x+18 | | 75-2x=3x+20 | | 9x+5= | | 4m+16n= | | 10m+5n-6m+11n= | | 4x+35= | | 6x-2=14x | | 219-4x=32x+19 | | -112-10x=9x+21 | | 87-4x=2x+21 | | 5x+7=87-5x |

Equations solver categories