-x^2-9x+18=

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


Simplifying
-1x2 + -9x + 18 = 0

Reorder the terms:
18 + -9x + -1x2 = 0

Solving
18 + -9x + -1x2 = 0

Solving for variable 'x'.

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

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

Move the constant term to the right:

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

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

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

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

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 = 18 + 20.25

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

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

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

Calculate the square root of the right side: 6.184658438

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

Subproblem 1

x + 4.5 = 6.184658438 Simplifying x + 4.5 = 6.184658438 Reorder the terms: 4.5 + x = 6.184658438 Solving 4.5 + x = 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 + x = 6.184658438 + -4.5 Combine like terms: 4.5 + -4.5 = 0.0 0.0 + x = 6.184658438 + -4.5 x = 6.184658438 + -4.5 Combine like terms: 6.184658438 + -4.5 = 1.684658438 x = 1.684658438 Simplifying x = 1.684658438

Subproblem 2

x + 4.5 = -6.184658438 Simplifying x + 4.5 = -6.184658438 Reorder the terms: 4.5 + x = -6.184658438 Solving 4.5 + x = -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 + x = -6.184658438 + -4.5 Combine like terms: 4.5 + -4.5 = 0.0 0.0 + x = -6.184658438 + -4.5 x = -6.184658438 + -4.5 Combine like terms: -6.184658438 + -4.5 = -10.684658438 x = -10.684658438 Simplifying x = -10.684658438

Solution

The solution to the problem is based on the solutions from the subproblems. x = {1.684658438, -10.684658438}

See similar equations:

| 3x^2-4=-16 | | 8+18n-2=5n+118-3n | | 2x^2+x-8+x=0 | | 3(x+2)+5(x+6)= | | -x^2-20x+51= | | -x^2-8x+7= | | -x^2+12x-32= | | n^2-3n=-5 | | 3m+8m=66 | | -x^2+7x-10= | | 30x-(6-x)+(4-5x)=-(5x+6) | | 9*-17= | | 7N-16=17+6N | | -x^2+19x-34= | | -10.7x=85.6 | | c^2+13c+42=0 | | 3M-10=2+2M | | 3v^2+28v+60=0 | | 30x+40y=280 | | -x^2+11x-30= | | x^2+8x+9=-7 | | x^2+24x+17=30 | | 9j-6h=-5h+1 | | 3.6q-5.5-4.6q=-2.0q-3.2 | | 30=-5(y+2) | | (5-x)-(6-4x)=8x-(3x-17) | | 14+8(4x-7)=5x-10 | | 4.5p+.5=7.25 | | 2x^2+3x=-2 | | A+2B=435 | | 2x+9=4x+11 | | 4(2-2x)+2=6(2x-6)-4x |

Equations solver categories