x^2-8x=18

Simple and best practice solution for x^2-8x=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^2-8x=18 equation:


Simplifying
x2 + -8x = 18

Reorder the terms:
-8x + x2 = 18

Solving
-8x + x2 = 18

Solving for variable 'x'.

Reorder the terms:
-18 + -8x + x2 = 18 + -18

Combine like terms: 18 + -18 = 0
-18 + -8x + x2 = 0

Begin completing the square.

Move the constant term to the right:

Add '18' to each side of the equation.
-18 + -8x + 18 + x2 = 0 + 18

Reorder the terms:
-18 + 18 + -8x + x2 = 0 + 18

Combine like terms: -18 + 18 = 0
0 + -8x + x2 = 0 + 18
-8x + x2 = 0 + 18

Combine like terms: 0 + 18 = 18
-8x + x2 = 18

The x term is -8x.  Take half its coefficient (-4).
Square it (16) and add it to both sides.

Add '16' to each side of the equation.
-8x + 16 + x2 = 18 + 16

Reorder the terms:
16 + -8x + x2 = 18 + 16

Combine like terms: 18 + 16 = 34
16 + -8x + x2 = 34

Factor a perfect square on the left side:
(x + -4)(x + -4) = 34

Calculate the square root of the right side: 5.830951895

Break this problem into two subproblems by setting 
(x + -4) equal to 5.830951895 and -5.830951895.

Subproblem 1

x + -4 = 5.830951895 Simplifying x + -4 = 5.830951895 Reorder the terms: -4 + x = 5.830951895 Solving -4 + x = 5.830951895 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '4' to each side of the equation. -4 + 4 + x = 5.830951895 + 4 Combine like terms: -4 + 4 = 0 0 + x = 5.830951895 + 4 x = 5.830951895 + 4 Combine like terms: 5.830951895 + 4 = 9.830951895 x = 9.830951895 Simplifying x = 9.830951895

Subproblem 2

x + -4 = -5.830951895 Simplifying x + -4 = -5.830951895 Reorder the terms: -4 + x = -5.830951895 Solving -4 + x = -5.830951895 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '4' to each side of the equation. -4 + 4 + x = -5.830951895 + 4 Combine like terms: -4 + 4 = 0 0 + x = -5.830951895 + 4 x = -5.830951895 + 4 Combine like terms: -5.830951895 + 4 = -1.830951895 x = -1.830951895 Simplifying x = -1.830951895

Solution

The solution to the problem is based on the solutions from the subproblems. x = {9.830951895, -1.830951895}

See similar equations:

| 16c-6-3c+4= | | 6x^2+17x-12= | | 3t+17=t+-3 | | 4x+8y=12 | | d-9=-25 | | 6x-.5(7-3x)=5.5 | | k^2-12k+20= | | .5x=8-2(-x-2) | | 2x^2+11x+12=0 | | x+4.6=8.8 | | x^2=-11 | | 9=-8x-7 | | 2(3-2x)-5(1+4x)=-7 | | 4+-6.1+0.6= | | 3m+1=6m-5 | | x^2-6x-55=0 | | x^2-x-3=0 | | 10-3x+7x=-6 | | 5.8+-15=-14 | | 3y+16=5y | | x^2-3x+1=0 | | y=.50+60+1.3 | | 3.1w+5=0.8+w | | -3+6=10y-14-9y | | 10(1-9x)+6(x-10)= | | 4k+24=6k-10 | | 2x+2=64 | | -v^3+7=22 | | 4(C+1)=-42 | | -13y=130 | | 3a-5= | | 1200=535+4.5n |

Equations solver categories