4x(x+2)=20-x

Simple and best practice solution for 4x(x+2)=20-x 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 4x(x+2)=20-x equation:


Simplifying
4x(x + 2) = 20 + -1x

Reorder the terms:
4x(2 + x) = 20 + -1x
(2 * 4x + x * 4x) = 20 + -1x
(8x + 4x2) = 20 + -1x

Solving
8x + 4x2 = 20 + -1x

Solving for variable 'x'.

Reorder the terms:
-20 + 8x + x + 4x2 = 20 + -1x + -20 + x

Combine like terms: 8x + x = 9x
-20 + 9x + 4x2 = 20 + -1x + -20 + x

Reorder the terms:
-20 + 9x + 4x2 = 20 + -20 + -1x + x

Combine like terms: 20 + -20 = 0
-20 + 9x + 4x2 = 0 + -1x + x
-20 + 9x + 4x2 = -1x + x

Combine like terms: -1x + x = 0
-20 + 9x + 4x2 = 0

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

Divide each side by '4'.
-5 + 2.25x + x2 = 0

Move the constant term to the right:

Add '5' to each side of the equation.
-5 + 2.25x + 5 + x2 = 0 + 5

Reorder the terms:
-5 + 5 + 2.25x + x2 = 0 + 5

Combine like terms: -5 + 5 = 0
0 + 2.25x + x2 = 0 + 5
2.25x + x2 = 0 + 5

Combine like terms: 0 + 5 = 5
2.25x + x2 = 5

The x term is 2.25x.  Take half its coefficient (1.125).
Square it (1.265625) and add it to both sides.

Add '1.265625' to each side of the equation.
2.25x + 1.265625 + x2 = 5 + 1.265625

Reorder the terms:
1.265625 + 2.25x + x2 = 5 + 1.265625

Combine like terms: 5 + 1.265625 = 6.265625
1.265625 + 2.25x + x2 = 6.265625

Factor a perfect square on the left side:
(x + 1.125)(x + 1.125) = 6.265625

Calculate the square root of the right side: 2.503123049

Break this problem into two subproblems by setting 
(x + 1.125) equal to 2.503123049 and -2.503123049.

Subproblem 1

x + 1.125 = 2.503123049 Simplifying x + 1.125 = 2.503123049 Reorder the terms: 1.125 + x = 2.503123049 Solving 1.125 + x = 2.503123049 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-1.125' to each side of the equation. 1.125 + -1.125 + x = 2.503123049 + -1.125 Combine like terms: 1.125 + -1.125 = 0.000 0.000 + x = 2.503123049 + -1.125 x = 2.503123049 + -1.125 Combine like terms: 2.503123049 + -1.125 = 1.378123049 x = 1.378123049 Simplifying x = 1.378123049

Subproblem 2

x + 1.125 = -2.503123049 Simplifying x + 1.125 = -2.503123049 Reorder the terms: 1.125 + x = -2.503123049 Solving 1.125 + x = -2.503123049 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-1.125' to each side of the equation. 1.125 + -1.125 + x = -2.503123049 + -1.125 Combine like terms: 1.125 + -1.125 = 0.000 0.000 + x = -2.503123049 + -1.125 x = -2.503123049 + -1.125 Combine like terms: -2.503123049 + -1.125 = -3.628123049 x = -3.628123049 Simplifying x = -3.628123049

Solution

The solution to the problem is based on the solutions from the subproblems. x = {1.378123049, -3.628123049}

See similar equations:

| k/4+1=9 | | x-38=27 | | 2x=6+3x | | 5(x-1)= | | x/6=8 | | t^2+6t-15=0 | | 6x+x^2=9 | | x^2=6+x | | 10x-12=12x-10 | | 4x+2y=2x+4y-2 | | 8m=4.4 | | x^2-y^2+4x-4y=0 | | 16x-3x=3 | | x^2+y^2-2x-2y=0 | | 5t^2+t=0 | | tan(x)-3=-4 | | lnx+2=1 | | y+12=x^2+x | | lograizx=log(x-2) | | 15x+6y=18 | | x-1+45+63=180 | | y+6+51+74=180 | | -19+-8= | | 3w^2-3w-588=0 | | (-19)+(-8)= | | .05(.3m+35n)-.8(-9n-22m)=0 | | 2x+85=180 | | (8-v)(4v-2)=0 | | -2w(w+3)(w+6)=0 | | -2w(w+3)=0 | | xln(2)=ln(22)-ln(10)+4ln(2) | | x=14(-6) |

Equations solver categories