2x^2-3x-8=0

Simple and best practice solution for 2x^2-3x-8=0 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 2x^2-3x-8=0 equation:


Simplifying
2x2 + -3x + -8 = 0

Reorder the terms:
-8 + -3x + 2x2 = 0

Solving
-8 + -3x + 2x2 = 0

Solving for variable 'x'.

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

Divide each side by '2'.
-4 + -1.5x + x2 = 0

Move the constant term to the right:

Add '4' to each side of the equation.
-4 + -1.5x + 4 + x2 = 0 + 4

Reorder the terms:
-4 + 4 + -1.5x + x2 = 0 + 4

Combine like terms: -4 + 4 = 0
0 + -1.5x + x2 = 0 + 4
-1.5x + x2 = 0 + 4

Combine like terms: 0 + 4 = 4
-1.5x + x2 = 4

The x term is -1.5x.  Take half its coefficient (-0.75).
Square it (0.5625) and add it to both sides.

Add '0.5625' to each side of the equation.
-1.5x + 0.5625 + x2 = 4 + 0.5625

Reorder the terms:
0.5625 + -1.5x + x2 = 4 + 0.5625

Combine like terms: 4 + 0.5625 = 4.5625
0.5625 + -1.5x + x2 = 4.5625

Factor a perfect square on the left side:
(x + -0.75)(x + -0.75) = 4.5625

Calculate the square root of the right side: 2.136000936

Break this problem into two subproblems by setting 
(x + -0.75) equal to 2.136000936 and -2.136000936.

Subproblem 1

x + -0.75 = 2.136000936 Simplifying x + -0.75 = 2.136000936 Reorder the terms: -0.75 + x = 2.136000936 Solving -0.75 + x = 2.136000936 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '0.75' to each side of the equation. -0.75 + 0.75 + x = 2.136000936 + 0.75 Combine like terms: -0.75 + 0.75 = 0.00 0.00 + x = 2.136000936 + 0.75 x = 2.136000936 + 0.75 Combine like terms: 2.136000936 + 0.75 = 2.886000936 x = 2.886000936 Simplifying x = 2.886000936

Subproblem 2

x + -0.75 = -2.136000936 Simplifying x + -0.75 = -2.136000936 Reorder the terms: -0.75 + x = -2.136000936 Solving -0.75 + x = -2.136000936 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '0.75' to each side of the equation. -0.75 + 0.75 + x = -2.136000936 + 0.75 Combine like terms: -0.75 + 0.75 = 0.00 0.00 + x = -2.136000936 + 0.75 x = -2.136000936 + 0.75 Combine like terms: -2.136000936 + 0.75 = -1.386000936 x = -1.386000936 Simplifying x = -1.386000936

Solution

The solution to the problem is based on the solutions from the subproblems. x = {2.886000936, -1.386000936}

See similar equations:

| 12.3x=28.29 | | 3x+12=78 | | -27+x=-27 | | 38-3x=6x+17 | | (-3w^2+w-4)+(5w^2+7w+2)= | | 0.6x=24 | | -90-9x=10x+24 | | 5(3n+10)=40n | | 72-2x=4x+6 | | 11p+18q+p-7q-3p= | | x+3=-6x-4 | | x+y=98 | | 10v=70 | | -7x=7 | | -3(2b-5)=-6b | | -18-10x=50-38x | | 13x+15000=Z-20345 | | 3c-24=6c(-4) | | b-36=-14 | | 140-3x=6x+23 | | r+-3=-5 | | 3x-7=33-7x | | 3x^2-2=-14 | | 3m=0 | | 0.7p=0.21 | | 3x+7=-17-9x | | -12x=-108 | | 2+7b-44=3b+12+9b | | x(8x+8)=3x^2-10+35 | | v^2+x=w^2 | | 2b+8b= | | 5c+40c= |

Equations solver categories