90=(2x)(x+15)

Simple and best practice solution for 90=(2x)(x+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 90=(2x)(x+15) equation: 


Simplifying
90 = (2x)(x + 15)

Remove parenthesis around (2x)
90 = 2x(x + 15)

Reorder the terms:
90 = 2x(15 + x)
90 = (15 * 2x + x * 2x)
90 = (30x + 2x2)

Solving
90 = 30x + 2x2

Solving for variable 'x'.

Reorder the terms:
90 + -30x + -2x2 = 30x + -30x + 2x2 + -2x2

Combine like terms: 30x + -30x = 0
90 + -30x + -2x2 = 0 + 2x2 + -2x2
90 + -30x + -2x2 = 2x2 + -2x2

Combine like terms: 2x2 + -2x2 = 0
90 + -30x + -2x2 = 0

Factor out the Greatest Common Factor (GCF), '2'.
2(45 + -15x + -1x2) = 0

Ignore the factor 2.

Subproblem 1
Set the factor '(45 + -15x + -1x2)' equal to zero and attempt to solve:

Simplifying
45 + -15x + -1x2 = 0

Solving
45 + -15x + -1x2 = 0

Begin completing the square.  Divide all terms by
-1 the coefficient of the squared term: 

Divide each side by '-1'.
-45 + 15x + x2 = 0

Move the constant term to the right:

Add '45' to each side of the equation.
-45 + 15x + 45 + x2 = 0 + 45

Reorder the terms:
-45 + 45 + 15x + x2 = 0 + 45

Combine like terms: -45 + 45 = 0
0 + 15x + x2 = 0 + 45
15x + x2 = 0 + 45

Combine like terms: 0 + 45 = 45
15x + x2 = 45

The x term is 15x.  Take half its coefficient (7.5).
Square it (56.25) and add it to both sides.

Add '56.25' to each side of the equation.
15x + 56.25 + x2 = 45 + 56.25

Reorder the terms:
56.25 + 15x + x2 = 45 + 56.25

Combine like terms: 45 + 56.25 = 101.25
56.25 + 15x + x2 = 101.25

Factor a perfect square on the left side:
(x + 7.5)(x + 7.5) = 101.25

Calculate the square root of the right side: 10.062305899

Break this problem into two subproblems by setting 
(x + 7.5) equal to 10.062305899 and -10.062305899.


Subproblem 1
x + 7.5 = 10.062305899

Simplifying
x + 7.5 = 10.062305899

Reorder the terms:
7.5 + x = 10.062305899

Solving
7.5 + x = 10.062305899

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '-7.5' to each side of the equation.
7.5 + -7.5 + x = 10.062305899 + -7.5

Combine like terms: 7.5 + -7.5 = 0.0
0.0 + x = 10.062305899 + -7.5
x = 10.062305899 + -7.5

Combine like terms: 10.062305899 + -7.5 = 2.562305899
x = 2.562305899

Simplifying
x = 2.562305899


Subproblem 2
x + 7.5 = -10.062305899

Simplifying
x + 7.5 = -10.062305899

Reorder the terms:
7.5 + x = -10.062305899

Solving
7.5 + x = -10.062305899

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '-7.5' to each side of the equation.
7.5 + -7.5 + x = -10.062305899 + -7.5

Combine like terms: 7.5 + -7.5 = 0.0
0.0 + x = -10.062305899 + -7.5
x = -10.062305899 + -7.5

Combine like terms: -10.062305899 + -7.5 = -17.562305899
x = -17.562305899

Simplifying
x = -17.562305899


Solution
The solution to the problem is based on the solutions
from the subproblems.
x = {2.562305899, -17.562305899}
Solution
x = {2.562305899, -17.562305899}

See similar equations:

| -8x+4+9x=-24+3 | | -5x-1=3x+63 | | -11x+8=-3x+72 | | (b+3)(b-3)= | | 7x+4-(2x+7)+3*(4-x)=15 | | (a-7)(a+7)= | | 2x+14=14x-82 | | 8(4a^2-5ab^2+ab)= | | 4x(x-5)=-2(x^2+3x) | | 5181180=15*480*(760-x) | | -12x-13=-8x-3 | | x-3=8x-7 | | (6x+2)(x-2)= | | 3x^2+24x-114=0 | | (2x-9)(x-11)= | | -6(3m+7)+3(m-7)= | | (y-6)(4y-1)= | | (3y-5)(2y-7)= | | (5x-6)(x+2)= | | 9a-4=77 | | 24+57= | | (y-12)(y+4)= | | 9(2x-3)+5=5(6-7x) | | 114/2= | | (x-5)(x+10)= | | (x+5)(x+1)= | | -9x=-18 | | 138-24= | | 5(4x+4)=20x+20 | | 8-x=9 | | 9x^2+14x-3=0 | | 4x-6=-20 |

Equations solver categories