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:

| 1.4-0.2=2.2 | | x^3-11x^2-250x+1400=0 | | x/22+16 | | a-2b=10forb | | x+50/2 | | (3x+31)+(2x-6)= | | 3+4+y=16 | | 18=4a+10x | | x+50/1 | | -5k+ar=r-7y | | 15=-3(2p-1) | | 55x+500=35x+500 | | -25+50/1 | | -7(x-8)=-x+38 | | 157=1x+8(18) | | 35=90 | | 2d+3=15 | | 45+2c=61+4c | | 16=-5+Z^4 | | (16/3)/2 | | 4/7*-4/7= | | 3/2a-8=-11 | | 16/3x2 | | 22-8.5= | | 269=11(157+-8y)+7y | | 16-3x=3(2-x) | | 9/5(-4)+32 | | -3(2-9)=6(q+1) | | 4(x+1)=6x | | 2(6p+6)=-84 | | 2(1-3x)+2(5x+4)=5-(4x-1) | | (x+5)+3x=40 |

Equations solver categories