7x^2+42x-2=0

Simple and best practice solution for 7x^2+42x-2=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 7x^2+42x-2=0 equation:


Simplifying
7x2 + 42x + -2 = 0

Reorder the terms:
-2 + 42x + 7x2 = 0

Solving
-2 + 42x + 7x2 = 0

Solving for variable 'x'.

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

Divide each side by '7'.
-0.2857142857 + 6x + x2 = 0

Move the constant term to the right:

Add '0.2857142857' to each side of the equation.
-0.2857142857 + 6x + 0.2857142857 + x2 = 0 + 0.2857142857

Reorder the terms:
-0.2857142857 + 0.2857142857 + 6x + x2 = 0 + 0.2857142857

Combine like terms: -0.2857142857 + 0.2857142857 = 0.0000000000
0.0000000000 + 6x + x2 = 0 + 0.2857142857
6x + x2 = 0 + 0.2857142857

Combine like terms: 0 + 0.2857142857 = 0.2857142857
6x + x2 = 0.2857142857

The x term is 6x.  Take half its coefficient (3).
Square it (9) and add it to both sides.

Add '9' to each side of the equation.
6x + 9 + x2 = 0.2857142857 + 9

Reorder the terms:
9 + 6x + x2 = 0.2857142857 + 9

Combine like terms: 0.2857142857 + 9 = 9.2857142857
9 + 6x + x2 = 9.2857142857

Factor a perfect square on the left side:
(x + 3)(x + 3) = 9.2857142857

Calculate the square root of the right side: 3.047247001

Break this problem into two subproblems by setting 
(x + 3) equal to 3.047247001 and -3.047247001.

Subproblem 1

x + 3 = 3.047247001 Simplifying x + 3 = 3.047247001 Reorder the terms: 3 + x = 3.047247001 Solving 3 + x = 3.047247001 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-3' to each side of the equation. 3 + -3 + x = 3.047247001 + -3 Combine like terms: 3 + -3 = 0 0 + x = 3.047247001 + -3 x = 3.047247001 + -3 Combine like terms: 3.047247001 + -3 = 0.047247001 x = 0.047247001 Simplifying x = 0.047247001

Subproblem 2

x + 3 = -3.047247001 Simplifying x + 3 = -3.047247001 Reorder the terms: 3 + x = -3.047247001 Solving 3 + x = -3.047247001 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-3' to each side of the equation. 3 + -3 + x = -3.047247001 + -3 Combine like terms: 3 + -3 = 0 0 + x = -3.047247001 + -3 x = -3.047247001 + -3 Combine like terms: -3.047247001 + -3 = -6.047247001 x = -6.047247001 Simplifying x = -6.047247001

Solution

The solution to the problem is based on the solutions from the subproblems. x = {0.047247001, -6.047247001}

See similar equations:

| 345+115y=255+130y | | y+(-8)=4 | | 308=22b | | 12c+5=-11 | | 3d+15=2d | | 13a+2=5a+8 | | 11+5m=86 | | 2g+2(-5+2g)=1-g | | 8(x+3)+11=15+2(x+35) | | 9x^2+16=65 | | -6+3u=-21 | | 6x*x=11 | | -5(x+4)+6x=-24 | | 345+115y=255+115y | | 3+6+7= | | -9(x+6)=18 | | 6(2x-7)=2(6x+8) | | n+(n-1)+(n-3)=36 | | -7+2v=-3 | | 3x-2.1=x+8.2 | | 2(2x-6)+15=11 | | 200=16-3n | | 75+12.40x=100+10x | | 3x+12=96-9x | | 2v+14=44 | | 3(3x+7)=-51 | | 3(2x+n)=22 | | -8(4x+7)=5(x+6)-2 | | f(-3)=0.7x^2-2.1x+6.6 | | -6(3x+11)=24 | | 5x-2y=x-3y+4 | | x^2-8x+y=0 |

Equations solver categories