4x^2-7x-8=

Simple and best practice solution for 4x^2-7x-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 4x^2-7x-8= equation:


Simplifying
4x2 + -7x + -8 = 0

Reorder the terms:
-8 + -7x + 4x2 = 0

Solving
-8 + -7x + 4x2 = 0

Solving for variable 'x'.

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

Divide each side by '4'.
-2 + -1.75x + x2 = 0

Move the constant term to the right:

Add '2' to each side of the equation.
-2 + -1.75x + 2 + x2 = 0 + 2

Reorder the terms:
-2 + 2 + -1.75x + x2 = 0 + 2

Combine like terms: -2 + 2 = 0
0 + -1.75x + x2 = 0 + 2
-1.75x + x2 = 0 + 2

Combine like terms: 0 + 2 = 2
-1.75x + x2 = 2

The x term is -1.75x.  Take half its coefficient (-0.875).
Square it (0.765625) and add it to both sides.

Add '0.765625' to each side of the equation.
-1.75x + 0.765625 + x2 = 2 + 0.765625

Reorder the terms:
0.765625 + -1.75x + x2 = 2 + 0.765625

Combine like terms: 2 + 0.765625 = 2.765625
0.765625 + -1.75x + x2 = 2.765625

Factor a perfect square on the left side:
(x + -0.875)(x + -0.875) = 2.765625

Calculate the square root of the right side: 1.663016837

Break this problem into two subproblems by setting 
(x + -0.875) equal to 1.663016837 and -1.663016837.

Subproblem 1

x + -0.875 = 1.663016837 Simplifying x + -0.875 = 1.663016837 Reorder the terms: -0.875 + x = 1.663016837 Solving -0.875 + x = 1.663016837 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '0.875' to each side of the equation. -0.875 + 0.875 + x = 1.663016837 + 0.875 Combine like terms: -0.875 + 0.875 = 0.000 0.000 + x = 1.663016837 + 0.875 x = 1.663016837 + 0.875 Combine like terms: 1.663016837 + 0.875 = 2.538016837 x = 2.538016837 Simplifying x = 2.538016837

Subproblem 2

x + -0.875 = -1.663016837 Simplifying x + -0.875 = -1.663016837 Reorder the terms: -0.875 + x = -1.663016837 Solving -0.875 + x = -1.663016837 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '0.875' to each side of the equation. -0.875 + 0.875 + x = -1.663016837 + 0.875 Combine like terms: -0.875 + 0.875 = 0.000 0.000 + x = -1.663016837 + 0.875 x = -1.663016837 + 0.875 Combine like terms: -1.663016837 + 0.875 = -0.788016837 x = -0.788016837 Simplifying x = -0.788016837

Solution

The solution to the problem is based on the solutions from the subproblems. x = {2.538016837, -0.788016837}

See similar equations:

| 2.5t-4.9t^2=58 | | (x^2)/(0.44-x) | | C=2(14)r | | 3-6(6-7x)=0 | | C=2j | | y^4-13y^2-1764=0 | | 1/14=560 | | 6x-3=12x-4 | | x/9=5/15 | | 7-2(4x+6)=3 | | 4x+2=7x-20 | | 10=(100-x)/x | | -4+2=7x-20 | | C=3.50+1.25(16m-1) | | 5/3=3z-5 | | 9x-80=433 | | (1/10000)x(1/160000)x(1/1296) | | 16x^2-16y^2= | | -3(-5-15x)= | | 1/20x1/20x1/20x1/20 | | 1/20x1/20x1/2x1/20 | | 1/6x1/6x1/6x1/6 | | 5y+10x=16 | | 4u^2+41u+45=0 | | 2ln(x-1)=ln(4x-7) | | (5/6)^-2 | | 6m-16=2m+52 | | 9n+15=5n+47 | | Y-z+2w=0 | | 8n=5n+12 | | X-y+w=0 | | 11k-2=5k-8 |

Equations solver categories