-2x^2+8x=5

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


Simplifying
-2x2 + 8x = 5

Reorder the terms:
8x + -2x2 = 5

Solving
8x + -2x2 = 5

Solving for variable 'x'.

Reorder the terms:
-5 + 8x + -2x2 = 5 + -5

Combine like terms: 5 + -5 = 0
-5 + 8x + -2x2 = 0

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

Divide each side by '-2'.
2.5 + -4x + x2 = 0

Move the constant term to the right:

Add '-2.5' to each side of the equation.
2.5 + -4x + -2.5 + x2 = 0 + -2.5

Reorder the terms:
2.5 + -2.5 + -4x + x2 = 0 + -2.5

Combine like terms: 2.5 + -2.5 = 0.0
0.0 + -4x + x2 = 0 + -2.5
-4x + x2 = 0 + -2.5

Combine like terms: 0 + -2.5 = -2.5
-4x + x2 = -2.5

The x term is -4x.  Take half its coefficient (-2).
Square it (4) and add it to both sides.

Add '4' to each side of the equation.
-4x + 4 + x2 = -2.5 + 4

Reorder the terms:
4 + -4x + x2 = -2.5 + 4

Combine like terms: -2.5 + 4 = 1.5
4 + -4x + x2 = 1.5

Factor a perfect square on the left side:
(x + -2)(x + -2) = 1.5

Calculate the square root of the right side: 1.224744871

Break this problem into two subproblems by setting 
(x + -2) equal to 1.224744871 and -1.224744871.

Subproblem 1

x + -2 = 1.224744871 Simplifying x + -2 = 1.224744871 Reorder the terms: -2 + x = 1.224744871 Solving -2 + x = 1.224744871 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '2' to each side of the equation. -2 + 2 + x = 1.224744871 + 2 Combine like terms: -2 + 2 = 0 0 + x = 1.224744871 + 2 x = 1.224744871 + 2 Combine like terms: 1.224744871 + 2 = 3.224744871 x = 3.224744871 Simplifying x = 3.224744871

Subproblem 2

x + -2 = -1.224744871 Simplifying x + -2 = -1.224744871 Reorder the terms: -2 + x = -1.224744871 Solving -2 + x = -1.224744871 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '2' to each side of the equation. -2 + 2 + x = -1.224744871 + 2 Combine like terms: -2 + 2 = 0 0 + x = -1.224744871 + 2 x = -1.224744871 + 2 Combine like terms: -1.224744871 + 2 = 0.775255129 x = 0.775255129 Simplifying x = 0.775255129

Solution

The solution to the problem is based on the solutions from the subproblems. x = {3.224744871, 0.775255129}

See similar equations:

| 10p^2-21p-10=0 | | 2x^2+x+9=0 | | x^2+4x=9 | | -5x^2+4x+2=0 | | 10z+x=180 | | 35=3-16x | | 2y=-3 | | r^2+r-156= | | 180-18z=x | | 3x^2-6x-1=0 | | -3+10y+6=15+12y-18 | | 2w^2+11w=-5 | | x^2-11x+2=0 | | 25x(x+2)=9000 | | 6u=-1 | | 25x^2+50-9000=0 | | x+(x+1)+(x+2)=108 | | -3x^2+7x-2=0 | | 7x-1=9x+7 | | x^3-3xy+2y^3=3 | | -5x^2-11x-2=0 | | y=-5x^2-11x-2 | | 3y+10=100-6x | | 2m+4x=6x-7 | | 2x-3(x+6)=-20 | | 2(0)+3y=-4 | | (3a-4a+7)-(5a-2a+1)= | | -3(x+5)+5x=11 | | 5x-9=3x+23 | | 4t-7=t+5 | | 2x-(-9)=4 | | -10x+5(-3x+5)=50 |

Equations solver categories