x(x+3)=20

Simple and best practice solution for x(x+3)=20 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(x+3)=20 equation:


Simplifying
x(x + 3) = 20

Reorder the terms:
x(3 + x) = 20
(3 * x + x * x) = 20
(3x + x2) = 20

Solving
3x + x2 = 20

Solving for variable 'x'.

Reorder the terms:
-20 + 3x + x2 = 20 + -20

Combine like terms: 20 + -20 = 0
-20 + 3x + x2 = 0

Begin completing the square.

Move the constant term to the right:

Add '20' to each side of the equation.
-20 + 3x + 20 + x2 = 0 + 20

Reorder the terms:
-20 + 20 + 3x + x2 = 0 + 20

Combine like terms: -20 + 20 = 0
0 + 3x + x2 = 0 + 20
3x + x2 = 0 + 20

Combine like terms: 0 + 20 = 20
3x + x2 = 20

The x term is 3x.  Take half its coefficient (1.5).
Square it (2.25) and add it to both sides.

Add '2.25' to each side of the equation.
3x + 2.25 + x2 = 20 + 2.25

Reorder the terms:
2.25 + 3x + x2 = 20 + 2.25

Combine like terms: 20 + 2.25 = 22.25
2.25 + 3x + x2 = 22.25

Factor a perfect square on the left side:
(x + 1.5)(x + 1.5) = 22.25

Calculate the square root of the right side: 4.716990566

Break this problem into two subproblems by setting 
(x + 1.5) equal to 4.716990566 and -4.716990566.

Subproblem 1

x + 1.5 = 4.716990566 Simplifying x + 1.5 = 4.716990566 Reorder the terms: 1.5 + x = 4.716990566 Solving 1.5 + x = 4.716990566 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-1.5' to each side of the equation. 1.5 + -1.5 + x = 4.716990566 + -1.5 Combine like terms: 1.5 + -1.5 = 0.0 0.0 + x = 4.716990566 + -1.5 x = 4.716990566 + -1.5 Combine like terms: 4.716990566 + -1.5 = 3.216990566 x = 3.216990566 Simplifying x = 3.216990566

Subproblem 2

x + 1.5 = -4.716990566 Simplifying x + 1.5 = -4.716990566 Reorder the terms: 1.5 + x = -4.716990566 Solving 1.5 + x = -4.716990566 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-1.5' to each side of the equation. 1.5 + -1.5 + x = -4.716990566 + -1.5 Combine like terms: 1.5 + -1.5 = 0.0 0.0 + x = -4.716990566 + -1.5 x = -4.716990566 + -1.5 Combine like terms: -4.716990566 + -1.5 = -6.216990566 x = -6.216990566 Simplifying x = -6.216990566

Solution

The solution to the problem is based on the solutions from the subproblems. x = {3.216990566, -6.216990566}

See similar equations:

| 9+76=16 | | -15g=9(-2g-17) | | 3x+.75=5.4 | | 14x^2+11x+2=0 | | -6.7y-15.2y+7=-10.7y-15.4 | | 3x+7=13+5x | | 0.8d+7.3=0.3d | | 3x+0.6=5.4 | | -15x^2+50x=0 | | 7.5+0.3y=5.4 | | 10=15x-2x | | 92-7x=11x+24 | | -(4x+10)-6=-3(x-2) | | 7x-6=2x-31 | | 1.1c+14.64=-15.39-c | | 3p-4+7p=66 | | -19.87+4.4n+10.98=14n-6.01 | | -9.8x^2/2 | | m/3-4=3m | | 4.1p=-7.8+3.7p | | 1+3z=35 | | 60=x+30 | | x^2/9+y^2/4=0 | | 3(x-6)=-10+3x | | 3c-5=3+2c+5 | | 2b=b | | -6x-5=-29+6x | | 21x^2=-12x | | 41=6x+(8x/2) | | 2B=12-2 | | -2y=45+7 | | C+72/9=25 |

Equations solver categories