8x^2+5x=18

Simple and best practice solution for 8x^2+5x=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 8x^2+5x=18 equation:


Simplifying
8x2 + 5x = 18

Reorder the terms:
5x + 8x2 = 18

Solving
5x + 8x2 = 18

Solving for variable 'x'.

Reorder the terms:
-18 + 5x + 8x2 = 18 + -18

Combine like terms: 18 + -18 = 0
-18 + 5x + 8x2 = 0

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

Divide each side by '8'.
-2.25 + 0.625x + x2 = 0

Move the constant term to the right:

Add '2.25' to each side of the equation.
-2.25 + 0.625x + 2.25 + x2 = 0 + 2.25

Reorder the terms:
-2.25 + 2.25 + 0.625x + x2 = 0 + 2.25

Combine like terms: -2.25 + 2.25 = 0.00
0.00 + 0.625x + x2 = 0 + 2.25
0.625x + x2 = 0 + 2.25

Combine like terms: 0 + 2.25 = 2.25
0.625x + x2 = 2.25

The x term is 0.625x.  Take half its coefficient (0.3125).
Square it (0.09765625) and add it to both sides.

Add '0.09765625' to each side of the equation.
0.625x + 0.09765625 + x2 = 2.25 + 0.09765625

Reorder the terms:
0.09765625 + 0.625x + x2 = 2.25 + 0.09765625

Combine like terms: 2.25 + 0.09765625 = 2.34765625
0.09765625 + 0.625x + x2 = 2.34765625

Factor a perfect square on the left side:
(x + 0.3125)(x + 0.3125) = 2.34765625

Calculate the square root of the right side: 1.532206334

Break this problem into two subproblems by setting 
(x + 0.3125) equal to 1.532206334 and -1.532206334.

Subproblem 1

x + 0.3125 = 1.532206334 Simplifying x + 0.3125 = 1.532206334 Reorder the terms: 0.3125 + x = 1.532206334 Solving 0.3125 + x = 1.532206334 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-0.3125' to each side of the equation. 0.3125 + -0.3125 + x = 1.532206334 + -0.3125 Combine like terms: 0.3125 + -0.3125 = 0.0000 0.0000 + x = 1.532206334 + -0.3125 x = 1.532206334 + -0.3125 Combine like terms: 1.532206334 + -0.3125 = 1.219706334 x = 1.219706334 Simplifying x = 1.219706334

Subproblem 2

x + 0.3125 = -1.532206334 Simplifying x + 0.3125 = -1.532206334 Reorder the terms: 0.3125 + x = -1.532206334 Solving 0.3125 + x = -1.532206334 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-0.3125' to each side of the equation. 0.3125 + -0.3125 + x = -1.532206334 + -0.3125 Combine like terms: 0.3125 + -0.3125 = 0.0000 0.0000 + x = -1.532206334 + -0.3125 x = -1.532206334 + -0.3125 Combine like terms: -1.532206334 + -0.3125 = -1.844706334 x = -1.844706334 Simplifying x = -1.844706334

Solution

The solution to the problem is based on the solutions from the subproblems. x = {1.219706334, -1.844706334}

See similar equations:

| -7x-1+5(x+1)=-7x-4 | | 9-4u=4 | | 1911-341= | | 5m+22=8m-5 | | 4x+3(3x-5)=8 | | y-10=1(x-2) | | f-4=f/3 | | -15t^2+150t+10=325 | | 4m+8=-5n | | 4x^2-27=0 | | y-2=5y+2-9y | | 14-8(5-s)+4(s+3)=30 | | x-1/5=10 | | 9x-48+900x=42 | | 2x^2=-21x-49 | | x^2-9=2x-6 | | 24x^2+38x+15=0 | | vy+7v-6y-42=o | | 9a-20=3a-4 | | -3k+13=2k-8 | | 27x=9 | | 2d+d=-12 | | W=Y(a+B) | | 0.5h+7=15 | | 3(x+2)=3[x-(4-x)] | | 2d+d=12 | | c^2+3c-40=0 | | 7x-4=11x+7 | | 2y^2+27y+25=(2y+25) | | 15x=-3 | | 16x^2-224=80x | | 7x-4=11x-4 |

Equations solver categories