18=x^4+9x^2

Simple and best practice solution for 18=x^4+9x^2 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 18=x^4+9x^2 equation:


Simplifying
18 = x4 + 9x2

Reorder the terms:
18 = 9x2 + x4

Solving
18 = 9x2 + x4

Solving for variable 'x'.

Reorder the terms:
18 + -9x2 + -1x4 = 9x2 + -9x2 + x4 + -1x4

Combine like terms: 9x2 + -9x2 = 0
18 + -9x2 + -1x4 = 0 + x4 + -1x4
18 + -9x2 + -1x4 = x4 + -1x4

Combine like terms: x4 + -1x4 = 0
18 + -9x2 + -1x4 = 0

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

Divide each side by '-1'.
-18 + 9x2 + x4 = 0

Move the constant term to the right:

Add '18' to each side of the equation.
-18 + 9x2 + 18 + x4 = 0 + 18

Reorder the terms:
-18 + 18 + 9x2 + x4 = 0 + 18

Combine like terms: -18 + 18 = 0
0 + 9x2 + x4 = 0 + 18
9x2 + x4 = 0 + 18

Combine like terms: 0 + 18 = 18
9x2 + x4 = 18

The x term is 9x2.  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.
9x2 + 20.25 + x4 = 18 + 20.25

Reorder the terms:
20.25 + 9x2 + x4 = 18 + 20.25

Combine like terms: 18 + 20.25 = 38.25
20.25 + 9x2 + x4 = 38.25

Factor a perfect square on the left side:
(x2 + 4.5)(x2 + 4.5) = 38.25

Calculate the square root of the right side: 6.184658438

Break this problem into two subproblems by setting 
(x2 + 4.5) equal to 6.184658438 and -6.184658438.

Subproblem 1

x2 + 4.5 = 6.184658438 Simplifying x2 + 4.5 = 6.184658438 Reorder the terms: 4.5 + x2 = 6.184658438 Solving 4.5 + x2 = 6.184658438 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 + x2 = 6.184658438 + -4.5 Combine like terms: 4.5 + -4.5 = 0.0 0.0 + x2 = 6.184658438 + -4.5 x2 = 6.184658438 + -4.5 Combine like terms: 6.184658438 + -4.5 = 1.684658438 x2 = 1.684658438 Simplifying x2 = 1.684658438 Take the square root of each side: x = {-1.297943927, 1.297943927}

Subproblem 2

x2 + 4.5 = -6.184658438 Simplifying x2 + 4.5 = -6.184658438 Reorder the terms: 4.5 + x2 = -6.184658438 Solving 4.5 + x2 = -6.184658438 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 + x2 = -6.184658438 + -4.5 Combine like terms: 4.5 + -4.5 = 0.0 0.0 + x2 = -6.184658438 + -4.5 x2 = -6.184658438 + -4.5 Combine like terms: -6.184658438 + -4.5 = -10.684658438 x2 = -10.684658438 Simplifying x2 = -10.684658438 Reorder the terms: 10.684658438 + x2 = -10.684658438 + 10.684658438 Combine like terms: -10.684658438 + 10.684658438 = 0.000000000 10.684658438 + x2 = 0.000000000 The solution to this equation could not be determined.This subproblem is being ignored because a solution could not be determined. The solution to this equation could not be determined.

See similar equations:

| 3x+40= | | 6[80s]= | | h^2+99h+18= | | 9n(5n+1)=0 | | m=8/5(4-9) | | 5x+19=2x+7 | | p^2+33n-18= | | 3x+4x+6x= | | x=3x+10 | | 6x-3=15+2 | | t^2+8t+12= | | 7x-15=4x+15 | | 5x+(4-x)=9(x-6) | | 4e-1=-93 | | 2x+33=3x | | -3(x+2)-5(x-3)=3(5x-2) | | 7.5d-7=53 | | 0.50x+0.70(40)=0.25(40) | | 7x+30=-5 | | -4+3(6+k)= | | a^2-9ab+20b^2= | | (24)(5)=(48)(t) | | 6-3(a-1)=1+a | | 4.4s+6.2=8.85s-1.8 | | 2+3w=5 | | (w+3)7= | | 16x-1=11x-21 | | 4x+39=x+15 | | p^2+9p+14=0 | | 11+5=-4(4x-4) | | 2x^2-13x-24=0 | | 3c+2.5= |

Equations solver categories