x^2-13x-20=0

Simple and best practice solution for x^2-13x-20=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^2-13x-20=0 equation:


Simplifying
x2 + -13x + -20 = 0

Reorder the terms:
-20 + -13x + x2 = 0

Solving
-20 + -13x + x2 = 0

Solving for variable 'x'.

Begin completing the square.

Move the constant term to the right:

Add '20' to each side of the equation.
-20 + -13x + 20 + x2 = 0 + 20

Reorder the terms:
-20 + 20 + -13x + x2 = 0 + 20

Combine like terms: -20 + 20 = 0
0 + -13x + x2 = 0 + 20
-13x + x2 = 0 + 20

Combine like terms: 0 + 20 = 20
-13x + x2 = 20

The x term is -13x.  Take half its coefficient (-6.5).
Square it (42.25) and add it to both sides.

Add '42.25' to each side of the equation.
-13x + 42.25 + x2 = 20 + 42.25

Reorder the terms:
42.25 + -13x + x2 = 20 + 42.25

Combine like terms: 20 + 42.25 = 62.25
42.25 + -13x + x2 = 62.25

Factor a perfect square on the left side:
(x + -6.5)(x + -6.5) = 62.25

Calculate the square root of the right side: 7.889866919

Break this problem into two subproblems by setting 
(x + -6.5) equal to 7.889866919 and -7.889866919.

Subproblem 1

x + -6.5 = 7.889866919 Simplifying x + -6.5 = 7.889866919 Reorder the terms: -6.5 + x = 7.889866919 Solving -6.5 + x = 7.889866919 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '6.5' to each side of the equation. -6.5 + 6.5 + x = 7.889866919 + 6.5 Combine like terms: -6.5 + 6.5 = 0.0 0.0 + x = 7.889866919 + 6.5 x = 7.889866919 + 6.5 Combine like terms: 7.889866919 + 6.5 = 14.389866919 x = 14.389866919 Simplifying x = 14.389866919

Subproblem 2

x + -6.5 = -7.889866919 Simplifying x + -6.5 = -7.889866919 Reorder the terms: -6.5 + x = -7.889866919 Solving -6.5 + x = -7.889866919 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '6.5' to each side of the equation. -6.5 + 6.5 + x = -7.889866919 + 6.5 Combine like terms: -6.5 + 6.5 = 0.0 0.0 + x = -7.889866919 + 6.5 x = -7.889866919 + 6.5 Combine like terms: -7.889866919 + 6.5 = -1.389866919 x = -1.389866919 Simplifying x = -1.389866919

Solution

The solution to the problem is based on the solutions from the subproblems. x = {14.389866919, -1.389866919}

See similar equations:

| -2n(2n+7)= | | 6(x-2)=9(x-7) | | 9x+12=2x+215 | | 1/3+4=x | | 1-2/-7-3= | | 2(4k+4)-18= | | -1*3c+4=7 | | 27-24x-12x+24x+32=11 | | x^3-9x^2+5x-45=0 | | 4(3t-5)-2(4-6t)= | | 1*3=x | | 1*3=x | | 3(c+3)-2=2(c+6)+2 | | -x+5=-12 | | x+4+=x+4 | | 0=16t^2-1150 | | 0=16t^2+1150 | | 2x-5+3x=36 | | 4a=-4 | | [-12]-[11-14]= | | -18x+4=36 | | 8x+95x=6 | | (3,-2)(-7,1)= | | 7(n-2)=21 | | 120/x=-7 | | 2x^2+7x-9x=0 | | 1/5x-1-4/5x-13 | | 0=5x^2-19x-30 | | -3x=63/7 | | 2x+3=23+6x | | X-26=15*2 | | 5+5x+7x-10=2x-5+20 |

Equations solver categories