4x^2+21x-27=0

Simple and best practice solution for 4x^2+21x-27=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 4x^2+21x-27=0 equation:


Simplifying
4x2 + 21x + -27 = 0

Reorder the terms:
-27 + 21x + 4x2 = 0

Solving
-27 + 21x + 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'.
-6.75 + 5.25x + x2 = 0

Move the constant term to the right:

Add '6.75' to each side of the equation.
-6.75 + 5.25x + 6.75 + x2 = 0 + 6.75

Reorder the terms:
-6.75 + 6.75 + 5.25x + x2 = 0 + 6.75

Combine like terms: -6.75 + 6.75 = 0.00
0.00 + 5.25x + x2 = 0 + 6.75
5.25x + x2 = 0 + 6.75

Combine like terms: 0 + 6.75 = 6.75
5.25x + x2 = 6.75

The x term is 5.25x.  Take half its coefficient (2.625).
Square it (6.890625) and add it to both sides.

Add '6.890625' to each side of the equation.
5.25x + 6.890625 + x2 = 6.75 + 6.890625

Reorder the terms:
6.890625 + 5.25x + x2 = 6.75 + 6.890625

Combine like terms: 6.75 + 6.890625 = 13.640625
6.890625 + 5.25x + x2 = 13.640625

Factor a perfect square on the left side:
(x + 2.625)(x + 2.625) = 13.640625

Calculate the square root of the right side: 3.693321676

Break this problem into two subproblems by setting 
(x + 2.625) equal to 3.693321676 and -3.693321676.

Subproblem 1

x + 2.625 = 3.693321676 Simplifying x + 2.625 = 3.693321676 Reorder the terms: 2.625 + x = 3.693321676 Solving 2.625 + x = 3.693321676 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-2.625' to each side of the equation. 2.625 + -2.625 + x = 3.693321676 + -2.625 Combine like terms: 2.625 + -2.625 = 0.000 0.000 + x = 3.693321676 + -2.625 x = 3.693321676 + -2.625 Combine like terms: 3.693321676 + -2.625 = 1.068321676 x = 1.068321676 Simplifying x = 1.068321676

Subproblem 2

x + 2.625 = -3.693321676 Simplifying x + 2.625 = -3.693321676 Reorder the terms: 2.625 + x = -3.693321676 Solving 2.625 + x = -3.693321676 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-2.625' to each side of the equation. 2.625 + -2.625 + x = -3.693321676 + -2.625 Combine like terms: 2.625 + -2.625 = 0.000 0.000 + x = -3.693321676 + -2.625 x = -3.693321676 + -2.625 Combine like terms: -3.693321676 + -2.625 = -6.318321676 x = -6.318321676 Simplifying x = -6.318321676

Solution

The solution to the problem is based on the solutions from the subproblems. x = {1.068321676, -6.318321676}

See similar equations:

| x=(7+2y)/3 | | x=3/4y-1 | | 2(3(125)-60)=x | | 1/4x | | 3x=14-x | | 6x^3+10x^2-24x= | | 2(3(125)-60)= | | 9-4x=8+5x | | 3(2x+1)-5=7 | | -3+10=m-3 | | 5m+7=7m-5 | | 4x-18=3x+8 | | 5*1/7 | | 5x=2x+7 | | S^2+3s=1 | | 2x-7x+7=0 | | f=n/15 | | v/88=6 | | x^2-150x+2250=0 | | 5m+10=50 | | ((4x^7y^-2)^2)/3z | | 18/25=x/1 | | y=2.5x+12 | | x^5-8x+9=0 | | 4/u+4=-7 | | 0.2(d-6)=0.3d+5-3+0.01d | | -4x-y=4 | | 9(x-1)-4x=21 | | x-2xy+3x=2 | | 3/4a-2/3a | | 20+x=2x | | 10-2x=5x |

Equations solver categories