x^2+20x-31=0

Simple and best practice solution for x^2+20x-31=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 x^2+20x-31=0 equation:


Simplifying
x2 + 20x + -31 = 0

Reorder the terms:
-31 + 20x + x2 = 0

Solving
-31 + 20x + x2 = 0

Solving for variable 'x'.

Begin completing the square.

Move the constant term to the right:

Add '31' to each side of the equation.
-31 + 20x + 31 + x2 = 0 + 31

Reorder the terms:
-31 + 31 + 20x + x2 = 0 + 31

Combine like terms: -31 + 31 = 0
0 + 20x + x2 = 0 + 31
20x + x2 = 0 + 31

Combine like terms: 0 + 31 = 31
20x + x2 = 31

The x term is 20x.  Take half its coefficient (10).
Square it (100) and add it to both sides.

Add '100' to each side of the equation.
20x + 100 + x2 = 31 + 100

Reorder the terms:
100 + 20x + x2 = 31 + 100

Combine like terms: 31 + 100 = 131
100 + 20x + x2 = 131

Factor a perfect square on the left side:
(x + 10)(x + 10) = 131

Calculate the square root of the right side: 11.445523142

Break this problem into two subproblems by setting 
(x + 10) equal to 11.445523142 and -11.445523142.

Subproblem 1

x + 10 = 11.445523142 Simplifying x + 10 = 11.445523142 Reorder the terms: 10 + x = 11.445523142 Solving 10 + x = 11.445523142 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-10' to each side of the equation. 10 + -10 + x = 11.445523142 + -10 Combine like terms: 10 + -10 = 0 0 + x = 11.445523142 + -10 x = 11.445523142 + -10 Combine like terms: 11.445523142 + -10 = 1.445523142 x = 1.445523142 Simplifying x = 1.445523142

Subproblem 2

x + 10 = -11.445523142 Simplifying x + 10 = -11.445523142 Reorder the terms: 10 + x = -11.445523142 Solving 10 + x = -11.445523142 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-10' to each side of the equation. 10 + -10 + x = -11.445523142 + -10 Combine like terms: 10 + -10 = 0 0 + x = -11.445523142 + -10 x = -11.445523142 + -10 Combine like terms: -11.445523142 + -10 = -21.445523142 x = -21.445523142 Simplifying x = -21.445523142

Solution

The solution to the problem is based on the solutions from the subproblems. x = {1.445523142, -21.445523142}

See similar equations:

| 10-(4y-2)=9-5y | | -4n+15=-4(n+5) | | -4.5x+2.2=-24.8 | | 5x-(-.5)=0.5-5x | | 12-5x=2y | | y=x^2-5x+9 | | z*4= | | 2x+6y=-42 | | X+8+7x= | | x^2+30x+21=0 | | r^2+16r-49=0 | | 0.6=0.33+f | | log(5-x)=0.5 | | 344.8= | | X+8+7x=40 | | 35x^2-333=0 | | 15+31=x | | (R^2)-4r=30 | | 23/40 | | ln(3x+1)=3.7 | | 0.2=0.25+f | | yx-12=7 | | 14x+5[6-(2x+3)]14x+5[6-(2x+3)]= | | 10x^2+5x-6=0 | | 0.1115898-1.3692x+4.2x^2=x^2 | | 3(x+2.28)=2x | | -16=2y+x | | 2x[7+6x(5+4)]=122 | | 2y+x=-16 | | -2(3x-4)=5(2x+3) | | x/4-16=-11 | | 200=10(x-50)+50 |

Equations solver categories