-0.8x^2-4x+28.8=

Simple and best practice solution for -0.8x^2-4x+28.8= 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 -0.8x^2-4x+28.8= equation:


Simplifying
-0.8x2 + -4x + 28.8 = 0

Reorder the terms:
28.8 + -4x + -0.8x2 = 0

Solving
28.8 + -4x + -0.8x2 = 0

Solving for variable 'x'.

Begin completing the square.  Divide all terms by
-0.8 the coefficient of the squared term: 

Divide each side by '-0.8'.
-36 + 5x + x2 = 0

Move the constant term to the right:

Add '36' to each side of the equation.
-36 + 5x + 36 + x2 = 0 + 36

Reorder the terms:
-36 + 36 + 5x + x2 = 0 + 36

Combine like terms: -36 + 36 = 0
0 + 5x + x2 = 0 + 36
5x + x2 = 0 + 36

Combine like terms: 0 + 36 = 36
5x + x2 = 36

The x term is 5x.  Take half its coefficient (2.5).
Square it (6.25) and add it to both sides.

Add '6.25' to each side of the equation.
5x + 6.25 + x2 = 36 + 6.25

Reorder the terms:
6.25 + 5x + x2 = 36 + 6.25

Combine like terms: 36 + 6.25 = 42.25
6.25 + 5x + x2 = 42.25

Factor a perfect square on the left side:
(x + 2.5)(x + 2.5) = 42.25

Calculate the square root of the right side: 6.5

Break this problem into two subproblems by setting 
(x + 2.5) equal to 6.5 and -6.5.

Subproblem 1

x + 2.5 = 6.5 Simplifying x + 2.5 = 6.5 Reorder the terms: 2.5 + x = 6.5 Solving 2.5 + x = 6.5 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-2.5' to each side of the equation. 2.5 + -2.5 + x = 6.5 + -2.5 Combine like terms: 2.5 + -2.5 = 0.0 0.0 + x = 6.5 + -2.5 x = 6.5 + -2.5 Combine like terms: 6.5 + -2.5 = 4 x = 4 Simplifying x = 4

Subproblem 2

x + 2.5 = -6.5 Simplifying x + 2.5 = -6.5 Reorder the terms: 2.5 + x = -6.5 Solving 2.5 + x = -6.5 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-2.5' to each side of the equation. 2.5 + -2.5 + x = -6.5 + -2.5 Combine like terms: 2.5 + -2.5 = 0.0 0.0 + x = -6.5 + -2.5 x = -6.5 + -2.5 Combine like terms: -6.5 + -2.5 = -9 x = -9 Simplifying x = -9

Solution

The solution to the problem is based on the solutions from the subproblems. x = {4, -9}

See similar equations:

| 7m=-5+2m | | 10sin^2(5x)=5 | | -(5x-3)=(3x+5) | | 6x^3-60x^2+54x= | | 2+7x=-2-70 | | 2x^3y+12x^2y+16xy= | | 4=x+5 | | 3(5-4)-4t=18 | | 78(150)+-4050= | | -(4+3x)=1 | | v^2-2vd-24d= | | 78(150)-4050= | | 3-x=2x-6 | | -3x^2-6x+24=0 | | 15x^2+35x= | | 78x-4050= | | (4+3x)=1 | | 19x+8+16x-3=180 | | y=12(0) | | 78x=4050 | | d+69=0 | | 4050x=78 | | 7x+5=26+26 | | y-8x=-4 | | 7p-5=6p | | 5x-y=-33 | | (3x-8)=4 | | 3x^3-18x^2+2=0 | | -(3x-8)=4 | | (6*-5)(6*-5)-(-2)(-2)= | | 2*-3-8= | | 25+6k=-1-5(k+8) |

Equations solver categories