8x^2-16x-15=0

Simple and best practice solution for 8x^2-16x-15=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 8x^2-16x-15=0 equation:


Simplifying
8x2 + -16x + -15 = 0

Reorder the terms:
-15 + -16x + 8x2 = 0

Solving
-15 + -16x + 8x2 = 0

Solving for variable 'x'.

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

Divide each side by '8'.
-1.875 + -2x + x2 = 0

Move the constant term to the right:

Add '1.875' to each side of the equation.
-1.875 + -2x + 1.875 + x2 = 0 + 1.875

Reorder the terms:
-1.875 + 1.875 + -2x + x2 = 0 + 1.875

Combine like terms: -1.875 + 1.875 = 0.000
0.000 + -2x + x2 = 0 + 1.875
-2x + x2 = 0 + 1.875

Combine like terms: 0 + 1.875 = 1.875
-2x + x2 = 1.875

The x term is -2x.  Take half its coefficient (-1).
Square it (1) and add it to both sides.

Add '1' to each side of the equation.
-2x + 1 + x2 = 1.875 + 1

Reorder the terms:
1 + -2x + x2 = 1.875 + 1

Combine like terms: 1.875 + 1 = 2.875
1 + -2x + x2 = 2.875

Factor a perfect square on the left side:
(x + -1)(x + -1) = 2.875

Calculate the square root of the right side: 1.695582496

Break this problem into two subproblems by setting 
(x + -1) equal to 1.695582496 and -1.695582496.

Subproblem 1

x + -1 = 1.695582496 Simplifying x + -1 = 1.695582496 Reorder the terms: -1 + x = 1.695582496 Solving -1 + x = 1.695582496 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '1' to each side of the equation. -1 + 1 + x = 1.695582496 + 1 Combine like terms: -1 + 1 = 0 0 + x = 1.695582496 + 1 x = 1.695582496 + 1 Combine like terms: 1.695582496 + 1 = 2.695582496 x = 2.695582496 Simplifying x = 2.695582496

Subproblem 2

x + -1 = -1.695582496 Simplifying x + -1 = -1.695582496 Reorder the terms: -1 + x = -1.695582496 Solving -1 + x = -1.695582496 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '1' to each side of the equation. -1 + 1 + x = -1.695582496 + 1 Combine like terms: -1 + 1 = 0 0 + x = -1.695582496 + 1 x = -1.695582496 + 1 Combine like terms: -1.695582496 + 1 = -0.695582496 x = -0.695582496 Simplifying x = -0.695582496

Solution

The solution to the problem is based on the solutions from the subproblems. x = {2.695582496, -0.695582496}

See similar equations:

| n+7-5n=19 | | 9w+9=3w-5 | | x^2-5.5x-3=0 | | 0.7=z/3 | | 3x-7=3y | | [(50)(40)]-[(26)(10)]=x | | 3(x)=(2)(1.1) | | P-32=.6P | | 44/60 | | y-0.25y=1944 | | 14x=x^2-15 | | (-3x+8)-(x^2+x-7)= | | 3m^2+21m=0 | | 0.3x+9.33=-0.8+5.83 | | 9w-12-2=7 | | 0.5x+3.79=-0.3x+2.39 | | 6x(2x-3y)= | | (-2z^3+z+2z^3+z)+(3z^3-5z^2)= | | 0.20y-0.6=0.10y+3-0.8y | | 15a+9=-5a+49 | | 24*24+18*18=c*c | | -0.5x+3.79=0.3x+2.39 | | 7xy+9xy=967 | | 2t-29=-13+4t | | d/dt(cos3t) | | 7.5+0.8x=0.3 | | 3x-2=5-x | | x-0.7=8.96 | | -4k-10x= | | 4/12-9/12 | | 26*24=40*(2x-4) | | 6(x+1.66)=5x |

Equations solver categories