x(x-9)=15

Simple and best practice solution for x(x-9)=15 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-9)=15 equation:


Simplifying
x(x + -9) = 15

Reorder the terms:
x(-9 + x) = 15
(-9 * x + x * x) = 15
(-9x + x2) = 15

Solving
-9x + x2 = 15

Solving for variable 'x'.

Reorder the terms:
-15 + -9x + x2 = 15 + -15

Combine like terms: 15 + -15 = 0
-15 + -9x + x2 = 0

Begin completing the square.

Move the constant term to the right:

Add '15' to each side of the equation.
-15 + -9x + 15 + x2 = 0 + 15

Reorder the terms:
-15 + 15 + -9x + x2 = 0 + 15

Combine like terms: -15 + 15 = 0
0 + -9x + x2 = 0 + 15
-9x + x2 = 0 + 15

Combine like terms: 0 + 15 = 15
-9x + x2 = 15

The x term is -9x.  Take half its coefficient (-4.5).
Square it (20.25) and add it to both sides.

Add '20.25' to each side of the equation.
-9x + 20.25 + x2 = 15 + 20.25

Reorder the terms:
20.25 + -9x + x2 = 15 + 20.25

Combine like terms: 15 + 20.25 = 35.25
20.25 + -9x + x2 = 35.25

Factor a perfect square on the left side:
(x + -4.5)(x + -4.5) = 35.25

Calculate the square root of the right side: 5.937171044

Break this problem into two subproblems by setting 
(x + -4.5) equal to 5.937171044 and -5.937171044.

Subproblem 1

x + -4.5 = 5.937171044 Simplifying x + -4.5 = 5.937171044 Reorder the terms: -4.5 + x = 5.937171044 Solving -4.5 + x = 5.937171044 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '4.5' to each side of the equation. -4.5 + 4.5 + x = 5.937171044 + 4.5 Combine like terms: -4.5 + 4.5 = 0.0 0.0 + x = 5.937171044 + 4.5 x = 5.937171044 + 4.5 Combine like terms: 5.937171044 + 4.5 = 10.437171044 x = 10.437171044 Simplifying x = 10.437171044

Subproblem 2

x + -4.5 = -5.937171044 Simplifying x + -4.5 = -5.937171044 Reorder the terms: -4.5 + x = -5.937171044 Solving -4.5 + x = -5.937171044 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '4.5' to each side of the equation. -4.5 + 4.5 + x = -5.937171044 + 4.5 Combine like terms: -4.5 + 4.5 = 0.0 0.0 + x = -5.937171044 + 4.5 x = -5.937171044 + 4.5 Combine like terms: -5.937171044 + 4.5 = -1.437171044 x = -1.437171044 Simplifying x = -1.437171044

Solution

The solution to the problem is based on the solutions from the subproblems. x = {10.437171044, -1.437171044}

See similar equations:

| 8=2x-5 | | 6x-75x=100 | | (3q-2)(q-7)=0 | | 3/7x=21 | | 4x^2-44x+112= | | (3p-2)(q-7)=0 | | 1/7/8/9 | | 3x+35x=76 | | 12x=2x | | -2+1=3x-5 | | 2/5h-7=12/5h-2h | | w+1/5=7/8 | | (9p-4)(p+9)=0 | | 8=4m-4 | | 4+(-3/5)x=16 | | n/0.6=662/3 | | 2p^3+30p^2-68p= | | 86-2x=60 | | 3/2X5/8 | | v+v+v+v+v+10= | | (8x)+(11x-1)=180 | | x-0.7=8.52 | | 11/2*5/8 | | 6x-21=-12+9x | | P+7/4=37/8 | | 1.5x5/8 | | 0.22y-2.5=0.12y+1-0.6y | | 2y^3+3y^2-50y-75= | | x+x^2=2 | | (4y-8)/(3y)=6 | | 1/2/2 | | (-8c^2+4c+6)-(6c^2+7c-3)= |

Equations solver categories