-x^2+20x-80=0

Simple and best practice solution for -x^2+20x-80=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-80=0 equation:


Simplifying
-1x2 + 20x + -80 = 0

Reorder the terms:
-80 + 20x + -1x2 = 0

Solving
-80 + 20x + -1x2 = 0

Solving for variable 'x'.

Begin completing the square.  Divide all terms by
-1 the coefficient of the squared term: 

Divide each side by '-1'.
80 + -20x + x2 = 0

Move the constant term to the right:

Add '-80' to each side of the equation.
80 + -20x + -80 + x2 = 0 + -80

Reorder the terms:
80 + -80 + -20x + x2 = 0 + -80

Combine like terms: 80 + -80 = 0
0 + -20x + x2 = 0 + -80
-20x + x2 = 0 + -80

Combine like terms: 0 + -80 = -80
-20x + x2 = -80

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 = -80 + 100

Reorder the terms:
100 + -20x + x2 = -80 + 100

Combine like terms: -80 + 100 = 20
100 + -20x + x2 = 20

Factor a perfect square on the left side:
(x + -10)(x + -10) = 20

Calculate the square root of the right side: 4.472135955

Break this problem into two subproblems by setting 
(x + -10) equal to 4.472135955 and -4.472135955.

Subproblem 1

x + -10 = 4.472135955 Simplifying x + -10 = 4.472135955 Reorder the terms: -10 + x = 4.472135955 Solving -10 + x = 4.472135955 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 = 4.472135955 + 10 Combine like terms: -10 + 10 = 0 0 + x = 4.472135955 + 10 x = 4.472135955 + 10 Combine like terms: 4.472135955 + 10 = 14.472135955 x = 14.472135955 Simplifying x = 14.472135955

Subproblem 2

x + -10 = -4.472135955 Simplifying x + -10 = -4.472135955 Reorder the terms: -10 + x = -4.472135955 Solving -10 + x = -4.472135955 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 = -4.472135955 + 10 Combine like terms: -10 + 10 = 0 0 + x = -4.472135955 + 10 x = -4.472135955 + 10 Combine like terms: -4.472135955 + 10 = 5.527864045 x = 5.527864045 Simplifying x = 5.527864045

Solution

The solution to the problem is based on the solutions from the subproblems. x = {14.472135955, 5.527864045}

See similar equations:

| X^4+6X^2+-5X^3+-30X=0 | | -1=-12+14a-17 | | y=x^2-2x-9 | | 2(3x+2)=3x+10 | | 3(6t+1)-9=t-(t+5) | | -12x-6(-9)=42 | | 3x+x-4=20 | | 4r+5=46r+11 | | 3(2Y+7)-11=4(Y+1) | | 9p-19p=-60 | | 2(g-2)-2=2(g-3) | | 9h+1h-6=5+2h-18 | | n^2+12=208 | | 8-k=7(k-4) | | 5n+3-8n=-5 | | x^2=tan(x) | | 15-8x+12= | | x^2=tanx | | -5(2-r)=20 | | -3+8x=-5 | | x-5=y^3 | | -2y+6y+x-4=0 | | (y+5)(y+7)=2 | | x^3-5x+9=0 | | 6x=8(4x+7) | | 28=-14+21 | | 28=-14 | | 12m-9=4m+14 | | 9-(-11)= | | a^2+-36=0 | | 3m+1=3m | | 9(4x-2)+16x=108 |

Equations solver categories