3x+9=2x(x-5)

Simple and best practice solution for 3x+9=2x(x-5) 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 3x+9=2x(x-5) equation:


Simplifying
3x + 9 = 2x(x + -5)

Reorder the terms:
9 + 3x = 2x(x + -5)

Reorder the terms:
9 + 3x = 2x(-5 + x)
9 + 3x = (-5 * 2x + x * 2x)
9 + 3x = (-10x + 2x2)

Solving
9 + 3x = -10x + 2x2

Solving for variable 'x'.

Combine like terms: 3x + 10x = 13x
9 + 13x + -2x2 = -10x + 2x2 + 10x + -2x2

Reorder the terms:
9 + 13x + -2x2 = -10x + 10x + 2x2 + -2x2

Combine like terms: -10x + 10x = 0
9 + 13x + -2x2 = 0 + 2x2 + -2x2
9 + 13x + -2x2 = 2x2 + -2x2

Combine like terms: 2x2 + -2x2 = 0
9 + 13x + -2x2 = 0

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

Divide each side by '-2'.
-4.5 + -6.5x + x2 = 0

Move the constant term to the right:

Add '4.5' to each side of the equation.
-4.5 + -6.5x + 4.5 + x2 = 0 + 4.5

Reorder the terms:
-4.5 + 4.5 + -6.5x + x2 = 0 + 4.5

Combine like terms: -4.5 + 4.5 = 0.0
0.0 + -6.5x + x2 = 0 + 4.5
-6.5x + x2 = 0 + 4.5

Combine like terms: 0 + 4.5 = 4.5
-6.5x + x2 = 4.5

The x term is -6.5x.  Take half its coefficient (-3.25).
Square it (10.5625) and add it to both sides.

Add '10.5625' to each side of the equation.
-6.5x + 10.5625 + x2 = 4.5 + 10.5625

Reorder the terms:
10.5625 + -6.5x + x2 = 4.5 + 10.5625

Combine like terms: 4.5 + 10.5625 = 15.0625
10.5625 + -6.5x + x2 = 15.0625

Factor a perfect square on the left side:
(x + -3.25)(x + -3.25) = 15.0625

Calculate the square root of the right side: 3.881043674

Break this problem into two subproblems by setting 
(x + -3.25) equal to 3.881043674 and -3.881043674.

Subproblem 1

x + -3.25 = 3.881043674 Simplifying x + -3.25 = 3.881043674 Reorder the terms: -3.25 + x = 3.881043674 Solving -3.25 + x = 3.881043674 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '3.25' to each side of the equation. -3.25 + 3.25 + x = 3.881043674 + 3.25 Combine like terms: -3.25 + 3.25 = 0.00 0.00 + x = 3.881043674 + 3.25 x = 3.881043674 + 3.25 Combine like terms: 3.881043674 + 3.25 = 7.131043674 x = 7.131043674 Simplifying x = 7.131043674

Subproblem 2

x + -3.25 = -3.881043674 Simplifying x + -3.25 = -3.881043674 Reorder the terms: -3.25 + x = -3.881043674 Solving -3.25 + x = -3.881043674 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '3.25' to each side of the equation. -3.25 + 3.25 + x = -3.881043674 + 3.25 Combine like terms: -3.25 + 3.25 = 0.00 0.00 + x = -3.881043674 + 3.25 x = -3.881043674 + 3.25 Combine like terms: -3.881043674 + 3.25 = -0.631043674 x = -0.631043674 Simplifying x = -0.631043674

Solution

The solution to the problem is based on the solutions from the subproblems. x = {7.131043674, -0.631043674}

See similar equations:

| 11f=121 | | 5(s+10)+5s=-70 | | 5x+0.3=40.3 | | x/5-13=1 | | 3i=-12 | | -10(x+4)=-5 | | 1+-2x=5 | | 2a-3b^2=c | | .79x+0.26=3.657 | | -16=11-9(y-9) | | -9x+1=-7 | | -17=3(p-4)+1 | | y/8=4=-2 | | 16y+21=133 | | 56=-6d+8 | | 9x=40-x | | 9x+1+88=180 | | X^7+90=24 | | 23=7r-5 | | 11*X+8=8*X-36 | | 100-16u/17u-5 | | 4a^3-9a^2=-5 | | 11*X-8=8*X+36 | | 0.825+26.95= | | -9(c-3)=90 | | 3m+n=p | | -6-x=6-3x | | 72=-6r-2r | | ((11*X)-8-36)/X=8 | | 26.95= | | m+785=1500 | | 3(t+2)=36 |

Equations solver categories