x^2+3x-18=11

Simple and best practice solution for x^2+3x-18=11 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^2+3x-18=11 equation:


Simplifying
x2 + 3x + -18 = 11

Reorder the terms:
-18 + 3x + x2 = 11

Solving
-18 + 3x + x2 = 11

Solving for variable 'x'.

Reorder the terms:
-18 + -11 + 3x + x2 = 11 + -11

Combine like terms: -18 + -11 = -29
-29 + 3x + x2 = 11 + -11

Combine like terms: 11 + -11 = 0
-29 + 3x + x2 = 0

Begin completing the square.

Move the constant term to the right:

Add '29' to each side of the equation.
-29 + 3x + 29 + x2 = 0 + 29

Reorder the terms:
-29 + 29 + 3x + x2 = 0 + 29

Combine like terms: -29 + 29 = 0
0 + 3x + x2 = 0 + 29
3x + x2 = 0 + 29

Combine like terms: 0 + 29 = 29
3x + x2 = 29

The x term is 3x.  Take half its coefficient (1.5).
Square it (2.25) and add it to both sides.

Add '2.25' to each side of the equation.
3x + 2.25 + x2 = 29 + 2.25

Reorder the terms:
2.25 + 3x + x2 = 29 + 2.25

Combine like terms: 29 + 2.25 = 31.25
2.25 + 3x + x2 = 31.25

Factor a perfect square on the left side:
(x + 1.5)(x + 1.5) = 31.25

Calculate the square root of the right side: 5.590169944

Break this problem into two subproblems by setting 
(x + 1.5) equal to 5.590169944 and -5.590169944.

Subproblem 1

x + 1.5 = 5.590169944 Simplifying x + 1.5 = 5.590169944 Reorder the terms: 1.5 + x = 5.590169944 Solving 1.5 + x = 5.590169944 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-1.5' to each side of the equation. 1.5 + -1.5 + x = 5.590169944 + -1.5 Combine like terms: 1.5 + -1.5 = 0.0 0.0 + x = 5.590169944 + -1.5 x = 5.590169944 + -1.5 Combine like terms: 5.590169944 + -1.5 = 4.090169944 x = 4.090169944 Simplifying x = 4.090169944

Subproblem 2

x + 1.5 = -5.590169944 Simplifying x + 1.5 = -5.590169944 Reorder the terms: 1.5 + x = -5.590169944 Solving 1.5 + x = -5.590169944 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-1.5' to each side of the equation. 1.5 + -1.5 + x = -5.590169944 + -1.5 Combine like terms: 1.5 + -1.5 = 0.0 0.0 + x = -5.590169944 + -1.5 x = -5.590169944 + -1.5 Combine like terms: -5.590169944 + -1.5 = -7.090169944 x = -7.090169944 Simplifying x = -7.090169944

Solution

The solution to the problem is based on the solutions from the subproblems. x = {4.090169944, -7.090169944}

See similar equations:

| 4x^2-9x+21=8x+6 | | x^4+10x^2+169x=0 | | xy*3=yx | | x^4=16x^2 | | y^2+4y-1=0 | | 25+y^3=150 | | x*4+8=54 | | x^5-5=27 | | 2y^3=432 | | 4y+3(7-y)=0 | | 4y+3(7-3)=0 | | 1x+(7)= | | 3x^2-12x+12= | | -(1+7x)-6(7-x)=36 | | 8x+11=2x+101 | | 11-7x=134-28x | | 4(g+2)+3g=15 | | 4(h+2)+2(4-h)=20 | | 2(e+1)-3=7 | | 7(5-d)=35 | | 3(2c-4)=0 | | 3(b-4)=15 | | 2(a+1)=10 | | 7(2x-3)=6(x-2)-3(2x+3) | | 12-0.5j=9 | | x(6x+4)=(2x+1)(2+3x) | | x-2y+20=0 | | 3(2+7x)-2-9x=11(2+x)+4x | | 11n-9=13 | | 3(4x+3)-7x=6(2+4x)-25x | | 3x+12=2(x+12)-1 | | 8t=5 |

Equations solver categories