7x^2-1=-2x

Simple and best practice solution for 7x^2-1=-2x 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 7x^2-1=-2x equation:


Simplifying
7x2 + -1 = -2x

Reorder the terms:
-1 + 7x2 = -2x

Solving
-1 + 7x2 = -2x

Solving for variable 'x'.

Reorder the terms:
-1 + 2x + 7x2 = -2x + 2x

Combine like terms: -2x + 2x = 0
-1 + 2x + 7x2 = 0

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

Divide each side by '7'.
-0.1428571429 + 0.2857142857x + x2 = 0

Move the constant term to the right:

Add '0.1428571429' to each side of the equation.
-0.1428571429 + 0.2857142857x + 0.1428571429 + x2 = 0 + 0.1428571429

Reorder the terms:
-0.1428571429 + 0.1428571429 + 0.2857142857x + x2 = 0 + 0.1428571429

Combine like terms: -0.1428571429 + 0.1428571429 = 0.0000000000
0.0000000000 + 0.2857142857x + x2 = 0 + 0.1428571429
0.2857142857x + x2 = 0 + 0.1428571429

Combine like terms: 0 + 0.1428571429 = 0.1428571429
0.2857142857x + x2 = 0.1428571429

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 = 0.1428571429 + 0.02040816328

Reorder the terms:
0.02040816328 + 0.2857142857x + x2 = 0.1428571429 + 0.02040816328

Combine like terms: 0.1428571429 + 0.02040816328 = 0.16326530618
0.02040816328 + 0.2857142857x + x2 = 0.16326530618

Factor a perfect square on the left side:
(x + 0.1428571429)(x + 0.1428571429) = 0.16326530618

Calculate the square root of the right side: 0.404061018

Break this problem into two subproblems by setting 
(x + 0.1428571429) equal to 0.404061018 and -0.404061018.

Subproblem 1

x + 0.1428571429 = 0.404061018 Simplifying x + 0.1428571429 = 0.404061018 Reorder the terms: 0.1428571429 + x = 0.404061018 Solving 0.1428571429 + x = 0.404061018 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 = 0.404061018 + -0.1428571429 Combine like terms: 0.1428571429 + -0.1428571429 = 0.0000000000 0.0000000000 + x = 0.404061018 + -0.1428571429 x = 0.404061018 + -0.1428571429 Combine like terms: 0.404061018 + -0.1428571429 = 0.2612038751 x = 0.2612038751 Simplifying x = 0.2612038751

Subproblem 2

x + 0.1428571429 = -0.404061018 Simplifying x + 0.1428571429 = -0.404061018 Reorder the terms: 0.1428571429 + x = -0.404061018 Solving 0.1428571429 + x = -0.404061018 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 = -0.404061018 + -0.1428571429 Combine like terms: 0.1428571429 + -0.1428571429 = 0.0000000000 0.0000000000 + x = -0.404061018 + -0.1428571429 x = -0.404061018 + -0.1428571429 Combine like terms: -0.404061018 + -0.1428571429 = -0.5469181609 x = -0.5469181609 Simplifying x = -0.5469181609

Solution

The solution to the problem is based on the solutions from the subproblems. x = {0.2612038751, -0.5469181609}

See similar equations:

| -85+3x=-4x+104 | | 7.75=a-16.187 | | 01/5(10h+15)+h | | 7(w+5)=9w+23 | | 3(5-2n)=7n-24 | | (3x-5)(x^2-6x+4)= | | -14=3w-8 | | 35x^2+x-12=0 | | 5y+2x=410 | | y-3/y^2-y+3/2y | | 35x+100=415 | | 2x+5y=410 | | -12b+4=52 | | 3211=16t^2 | | x(2)-x^2-5x-25=0 | | 2x+7x+10=0 | | 3=7n+6-3 | | (8x+9y)(8x-9y)= | | x/2+3x/4=-9 | | 6d+7=19 | | 24w^6+24w^3=0 | | 11X-2=72 | | 5-p=20 | | 3=m-[-2] | | 6x+2(-4x-16)=-54 | | -64-25-9= | | 14=-7a | | xy-4y=21996 | | X=-3-13x | | 12000=.8(v)-.08(v)(6) | | (20x^2+23x-7)/x-1 | | (X-6)=-12 |

Equations solver categories