x^2-13x=42

Simple and best practice solution for x^2-13x=42 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=42 equation:


Simplifying
x2 + -13x = 42

Reorder the terms:
-13x + x2 = 42

Solving
-13x + x2 = 42

Solving for variable 'x'.

Reorder the terms:
-42 + -13x + x2 = 42 + -42

Combine like terms: 42 + -42 = 0
-42 + -13x + x2 = 0

Begin completing the square.

Move the constant term to the right:

Add '42' to each side of the equation.
-42 + -13x + 42 + x2 = 0 + 42

Reorder the terms:
-42 + 42 + -13x + x2 = 0 + 42

Combine like terms: -42 + 42 = 0
0 + -13x + x2 = 0 + 42
-13x + x2 = 0 + 42

Combine like terms: 0 + 42 = 42
-13x + x2 = 42

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 = 42 + 42.25

Reorder the terms:
42.25 + -13x + x2 = 42 + 42.25

Combine like terms: 42 + 42.25 = 84.25
42.25 + -13x + x2 = 84.25

Factor a perfect square on the left side:
(x + -6.5)(x + -6.5) = 84.25

Calculate the square root of the right side: 9.178779875

Break this problem into two subproblems by setting 
(x + -6.5) equal to 9.178779875 and -9.178779875.

Subproblem 1

x + -6.5 = 9.178779875 Simplifying x + -6.5 = 9.178779875 Reorder the terms: -6.5 + x = 9.178779875 Solving -6.5 + x = 9.178779875 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 = 9.178779875 + 6.5 Combine like terms: -6.5 + 6.5 = 0.0 0.0 + x = 9.178779875 + 6.5 x = 9.178779875 + 6.5 Combine like terms: 9.178779875 + 6.5 = 15.678779875 x = 15.678779875 Simplifying x = 15.678779875

Subproblem 2

x + -6.5 = -9.178779875 Simplifying x + -6.5 = -9.178779875 Reorder the terms: -6.5 + x = -9.178779875 Solving -6.5 + x = -9.178779875 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 = -9.178779875 + 6.5 Combine like terms: -6.5 + 6.5 = 0.0 0.0 + x = -9.178779875 + 6.5 x = -9.178779875 + 6.5 Combine like terms: -9.178779875 + 6.5 = -2.678779875 x = -2.678779875 Simplifying x = -2.678779875

Solution

The solution to the problem is based on the solutions from the subproblems. x = {15.678779875, -2.678779875}

See similar equations:

| a(2x-2)=6a | | 9h-14=76 | | -13=-14+n/8 | | 3k-9k-8k+6=-64 | | Y^2-11y-38=0 | | 4(x+3)-8=16 | | (10-3)-((1-3)b)=(7-2)-((1-2)b) | | x-7y=-95 | | 10(-15+3y)+150=30y | | x-7y=95 | | .9x+.11x(5000-x)=487 | | 7x+2y=32 | | a+100=92 | | 2x=-30+6y | | d^2+16d+11=0 | | 5y^2-y+5=0 | | h-5t^2=0 | | (X+8)(x-3)(x-4-5i)(x-4+5i)=0 | | (4ab+2)(3ab-7)= | | 12y-(4y+10)=54 | | 2(t-8)=60 | | 36x+12y=60 | | 2t-8=60 | | 3x+5=4+7x+4 | | 9x^2+10x=1 | | (50)(1)=y(36.5/100) | | 4x+b=-2x-a | | (50)(1)=167(x/100) | | -4+x=0 | | (50)(1)=152(x/100) | | 2z+-3=-20 | | (50)(1)=154(x/100) |

Equations solver categories