x^2+9x-40=0

Simple and best practice solution for x^2+9x-40=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+9x-40=0 equation:


Simplifying
x2 + 9x + -40 = 0

Reorder the terms:
-40 + 9x + x2 = 0

Solving
-40 + 9x + x2 = 0

Solving for variable 'x'.

Begin completing the square.

Move the constant term to the right:

Add '40' to each side of the equation.
-40 + 9x + 40 + x2 = 0 + 40

Reorder the terms:
-40 + 40 + 9x + x2 = 0 + 40

Combine like terms: -40 + 40 = 0
0 + 9x + x2 = 0 + 40
9x + x2 = 0 + 40

Combine like terms: 0 + 40 = 40
9x + x2 = 40

The x term is 9x.  Take half its coefficient (4.5).
Square it (20.25) and add it to both sides.

Add '20.25' to each side of the equation.
9x + 20.25 + x2 = 40 + 20.25

Reorder the terms:
20.25 + 9x + x2 = 40 + 20.25

Combine like terms: 40 + 20.25 = 60.25
20.25 + 9x + x2 = 60.25

Factor a perfect square on the left side:
(x + 4.5)(x + 4.5) = 60.25

Calculate the square root of the right side: 7.762087348

Break this problem into two subproblems by setting 
(x + 4.5) equal to 7.762087348 and -7.762087348.

Subproblem 1

x + 4.5 = 7.762087348 Simplifying x + 4.5 = 7.762087348 Reorder the terms: 4.5 + x = 7.762087348 Solving 4.5 + x = 7.762087348 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-4.5' to each side of the equation. 4.5 + -4.5 + x = 7.762087348 + -4.5 Combine like terms: 4.5 + -4.5 = 0.0 0.0 + x = 7.762087348 + -4.5 x = 7.762087348 + -4.5 Combine like terms: 7.762087348 + -4.5 = 3.262087348 x = 3.262087348 Simplifying x = 3.262087348

Subproblem 2

x + 4.5 = -7.762087348 Simplifying x + 4.5 = -7.762087348 Reorder the terms: 4.5 + x = -7.762087348 Solving 4.5 + x = -7.762087348 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-4.5' to each side of the equation. 4.5 + -4.5 + x = -7.762087348 + -4.5 Combine like terms: 4.5 + -4.5 = 0.0 0.0 + x = -7.762087348 + -4.5 x = -7.762087348 + -4.5 Combine like terms: -7.762087348 + -4.5 = -12.262087348 x = -12.262087348 Simplifying x = -12.262087348

Solution

The solution to the problem is based on the solutions from the subproblems. x = {3.262087348, -12.262087348}

See similar equations:

| p^4-625=0 | | 4x-12y=28 | | 6-9x=2x-17 | | 3p/8-13=-25 | | 3x^2-x-14= | | 5-4x=x-20 | | 2(y+5)=4y-8 | | 6374848-63739= | | 2a^2+11ab+5b^2=0 | | 4m^2+5m=0 | | 9(x-2)=-12(2x-4) | | a^2-10a-ay+10y= | | t^2-17t+6=0 | | t^2-17y+6=0 | | 2y+1=5y-5 | | 21x^2+47x+20=0 | | 45x^3+123x^2+42x=0 | | 12(2x-3)=4(6x+5) | | -5=4(x+4)-3x | | w^2-d^2= | | 3(x-1)=-4x+36 | | (x)2+7x+12=0 | | 8x^2+48x-56= | | 1(x+2)+33=-4x | | (1/4)(3x+27)=3x | | (1/3)(3x-36)=5x | | r^3-6r^2-36r+216= | | -a-6=9 | | 35+12x+x^2=0 | | a^2-12ab+32b^2=0 | | v^3+22v^2+121v= | | -4x+7=19 |

Equations solver categories