2x^2+21x+36=0

Simple and best practice solution for 2x^2+21x+36=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 2x^2+21x+36=0 equation:


Simplifying
2x2 + 21x + 36 = 0

Reorder the terms:
36 + 21x + 2x2 = 0

Solving
36 + 21x + 2x2 = 0

Solving for variable 'x'.

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

Divide each side by '2'.
18 + 10.5x + x2 = 0

Move the constant term to the right:

Add '-18' to each side of the equation.
18 + 10.5x + -18 + x2 = 0 + -18

Reorder the terms:
18 + -18 + 10.5x + x2 = 0 + -18

Combine like terms: 18 + -18 = 0
0 + 10.5x + x2 = 0 + -18
10.5x + x2 = 0 + -18

Combine like terms: 0 + -18 = -18
10.5x + x2 = -18

The x term is 10.5x.  Take half its coefficient (5.25).
Square it (27.5625) and add it to both sides.

Add '27.5625' to each side of the equation.
10.5x + 27.5625 + x2 = -18 + 27.5625

Reorder the terms:
27.5625 + 10.5x + x2 = -18 + 27.5625

Combine like terms: -18 + 27.5625 = 9.5625
27.5625 + 10.5x + x2 = 9.5625

Factor a perfect square on the left side:
(x + 5.25)(x + 5.25) = 9.5625

Calculate the square root of the right side: 3.092329219

Break this problem into two subproblems by setting 
(x + 5.25) equal to 3.092329219 and -3.092329219.

Subproblem 1

x + 5.25 = 3.092329219 Simplifying x + 5.25 = 3.092329219 Reorder the terms: 5.25 + x = 3.092329219 Solving 5.25 + x = 3.092329219 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-5.25' to each side of the equation. 5.25 + -5.25 + x = 3.092329219 + -5.25 Combine like terms: 5.25 + -5.25 = 0.00 0.00 + x = 3.092329219 + -5.25 x = 3.092329219 + -5.25 Combine like terms: 3.092329219 + -5.25 = -2.157670781 x = -2.157670781 Simplifying x = -2.157670781

Subproblem 2

x + 5.25 = -3.092329219 Simplifying x + 5.25 = -3.092329219 Reorder the terms: 5.25 + x = -3.092329219 Solving 5.25 + x = -3.092329219 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-5.25' to each side of the equation. 5.25 + -5.25 + x = -3.092329219 + -5.25 Combine like terms: 5.25 + -5.25 = 0.00 0.00 + x = -3.092329219 + -5.25 x = -3.092329219 + -5.25 Combine like terms: -3.092329219 + -5.25 = -8.342329219 x = -8.342329219 Simplifying x = -8.342329219

Solution

The solution to the problem is based on the solutions from the subproblems. x = {-2.157670781, -8.342329219}

See similar equations:

| 0.15(x+60)-0.04(x-40)=4 | | 6x*4y=0 | | 10a+8=9a+18 | | 4x^3+21x^2+36x=20 | | 6x*6y=0 | | 8y+6x=20 | | 5x+14-2x^2=0 | | G(12)=3x-9 | | y=3x+24+15x+69 | | y=3x+24+4x+36 | | 2w-6x-y+6w+20x-5y= | | 2ln(x-2)=ln(x+2)+ln(9) | | 6x-2y+14w-4y-6w+8x= | | Ln(3x+9)=0 | | 5.6s+2.4(s+14)=49.60 | | h*30.750+(40-22.5)+h*3.503*(38-22.5)+h*17.775*(40-22.5)+h*6.358*(40-22.5)+h*30.750*(36-22.5)=1.602 | | 2y-4(2y-5)=6(y+3)-10 | | 3x-6=x-7 | | F(x)=1.5+12 | | 5w+6y+10x+4x-12y+3w= | | 2.4+5.6(14-x)=4960 | | 14x-50=14x-49-1 | | 90x^10=0 | | 6w-3=2w+14 | | s+31/2+20=74 | | 6x-5x+1=x-1 | | 3w+2x-13y+5w+12x+7y= | | 6m+12t= | | 25x-7=15x+7 | | A+2c=34 | | mx^2-2mx+1=0 | | 6x-2y+7=24z |

Equations solver categories