x^2+7x-x=20

Simple and best practice solution for x^2+7x-x=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 x^2+7x-x=20 equation:


Simplifying
x2 + 7x + -1x = 20

Reorder the terms:
7x + -1x + x2 = 20

Combine like terms: 7x + -1x = 6x
6x + x2 = 20

Solving
6x + x2 = 20

Solving for variable 'x'.

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

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

Begin completing the square.

Move the constant term to the right:

Add '20' to each side of the equation.
-20 + 6x + 20 + x2 = 0 + 20

Reorder the terms:
-20 + 20 + 6x + x2 = 0 + 20

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

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

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 = 20 + 9

Reorder the terms:
9 + 6x + x2 = 20 + 9

Combine like terms: 20 + 9 = 29
9 + 6x + x2 = 29

Factor a perfect square on the left side:
(x + 3)(x + 3) = 29

Calculate the square root of the right side: 5.385164807

Break this problem into two subproblems by setting 
(x + 3) equal to 5.385164807 and -5.385164807.

Subproblem 1

x + 3 = 5.385164807 Simplifying x + 3 = 5.385164807 Reorder the terms: 3 + x = 5.385164807 Solving 3 + x = 5.385164807 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 = 5.385164807 + -3 Combine like terms: 3 + -3 = 0 0 + x = 5.385164807 + -3 x = 5.385164807 + -3 Combine like terms: 5.385164807 + -3 = 2.385164807 x = 2.385164807 Simplifying x = 2.385164807

Subproblem 2

x + 3 = -5.385164807 Simplifying x + 3 = -5.385164807 Reorder the terms: 3 + x = -5.385164807 Solving 3 + x = -5.385164807 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 = -5.385164807 + -3 Combine like terms: 3 + -3 = 0 0 + x = -5.385164807 + -3 x = -5.385164807 + -3 Combine like terms: -5.385164807 + -3 = -8.385164807 x = -8.385164807 Simplifying x = -8.385164807

Solution

The solution to the problem is based on the solutions from the subproblems. x = {2.385164807, -8.385164807}

See similar equations:

| 7r=90.93 | | 2(a+3)=(-3a+6) | | u-17/3=1 | | 4(x+5)=-10(x-3) | | 4(3w+2)=2(5w+8) | | -8z=8-7z | | 6x+1=86 | | c+10-3= -2 | | -q=-3-4q | | 13.352=3.338-8Y*(4)+Y(32) | | b+10=3b-10 | | -9(9-3y)= | | 5x=-7x-48 | | -12x+13y=-10 | | 21x-5=147 | | -8-4d=-3d | | -3(t-4)+6t=9t-5 | | 2x+53=9x-10 | | -30=-3x-7x | | 10x-3=90 | | Log(y)=1.2+2.4 | | 6x^2-24x+27=0 | | -1.5-9=0 | | 7x+15=3x+35 | | -9j+4=-5j | | 13.352=(3.338-8Y)*(4)+Y(32) | | -x+4=47 | | 3(n+7)-8=1 | | -9x-23=x-87 | | -0.7x+2=65 | | 78=3.1416*R^2 | | 9j+4=5j |

Equations solver categories