0=x^2-4x-40

Simple and best practice solution for 0=x^2-4x-40 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 0=x^2-4x-40 equation:


Simplifying
0 = x2 + -4x + -40

Reorder the terms:
0 = -40 + -4x + x2

Solving
0 = -40 + -4x + x2

Solving for variable 'x'.

Combine like terms: 0 + 40 = 40
40 + 4x + -1x2 = -40 + -4x + x2 + 40 + 4x + -1x2

Reorder the terms:
40 + 4x + -1x2 = -40 + 40 + -4x + 4x + x2 + -1x2

Combine like terms: -40 + 40 = 0
40 + 4x + -1x2 = 0 + -4x + 4x + x2 + -1x2
40 + 4x + -1x2 = -4x + 4x + x2 + -1x2

Combine like terms: -4x + 4x = 0
40 + 4x + -1x2 = 0 + x2 + -1x2
40 + 4x + -1x2 = x2 + -1x2

Combine like terms: x2 + -1x2 = 0
40 + 4x + -1x2 = 0

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

Divide each side by '-1'.
-40 + -4x + x2 = 0

Move the constant term to the right:

Add '40' to each side of the equation.
-40 + -4x + 40 + x2 = 0 + 40

Reorder the terms:
-40 + 40 + -4x + x2 = 0 + 40

Combine like terms: -40 + 40 = 0
0 + -4x + x2 = 0 + 40
-4x + x2 = 0 + 40

Combine like terms: 0 + 40 = 40
-4x + x2 = 40

The x term is -4x.  Take half its coefficient (-2).
Square it (4) and add it to both sides.

Add '4' to each side of the equation.
-4x + 4 + x2 = 40 + 4

Reorder the terms:
4 + -4x + x2 = 40 + 4

Combine like terms: 40 + 4 = 44
4 + -4x + x2 = 44

Factor a perfect square on the left side:
(x + -2)(x + -2) = 44

Calculate the square root of the right side: 6.633249581

Break this problem into two subproblems by setting 
(x + -2) equal to 6.633249581 and -6.633249581.

Subproblem 1

x + -2 = 6.633249581 Simplifying x + -2 = 6.633249581 Reorder the terms: -2 + x = 6.633249581 Solving -2 + x = 6.633249581 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '2' to each side of the equation. -2 + 2 + x = 6.633249581 + 2 Combine like terms: -2 + 2 = 0 0 + x = 6.633249581 + 2 x = 6.633249581 + 2 Combine like terms: 6.633249581 + 2 = 8.633249581 x = 8.633249581 Simplifying x = 8.633249581

Subproblem 2

x + -2 = -6.633249581 Simplifying x + -2 = -6.633249581 Reorder the terms: -2 + x = -6.633249581 Solving -2 + x = -6.633249581 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '2' to each side of the equation. -2 + 2 + x = -6.633249581 + 2 Combine like terms: -2 + 2 = 0 0 + x = -6.633249581 + 2 x = -6.633249581 + 2 Combine like terms: -6.633249581 + 2 = -4.633249581 x = -4.633249581 Simplifying x = -4.633249581

Solution

The solution to the problem is based on the solutions from the subproblems. x = {8.633249581, -4.633249581}

See similar equations:

| H(x)=(7x+6)4 | | 5x+86=3x+138 | | 6r^2+3r-5= | | x^2+2y^2-2x+8y-9=0 | | 6n+7-2n=-1 | | 28y+1=9 | | 8x+4=88 | | log^8x+log^8(x+12)=2 | | -3m-8=-20 | | 2(5x-1)=3(3x+11) | | 10h+7=97 | | log(2x)=3 | | Y=(7x-3)(9x-5) | | 30x^2+2000=-20x^2-2050 | | -5x=3y-2 | | 30x^2+270=0 | | 3y+x=-5 | | x^2+6x+9+x^2=x^2+49 | | 2x-5+3x+4=24 | | -x=3y+4 | | ||x-3||-5|=4 | | (2u^2-3u+6)+(-4u^2+u+5)= | | 1-4v-3-12=6v-4 | | 2x-9y=-57 | | C=zs+z | | y=cos*4*x | | |x+2|=0,8(3) | | 6x+2y=140 | | X^4-x^3+8x-8=0 | | |x+2|=8,(3) | | (2x-3)(3x+1)= | | 3tan^2x=1 |

Equations solver categories