4x^2+2x=-21

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


Simplifying
4x2 + 2x = -21

Reorder the terms:
2x + 4x2 = -21

Solving
2x + 4x2 = -21

Solving for variable 'x'.

Reorder the terms:
21 + 2x + 4x2 = -21 + 21

Combine like terms: -21 + 21 = 0
21 + 2x + 4x2 = 0

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

Divide each side by '4'.
5.25 + 0.5x + x2 = 0

Move the constant term to the right:

Add '-5.25' to each side of the equation.
5.25 + 0.5x + -5.25 + x2 = 0 + -5.25

Reorder the terms:
5.25 + -5.25 + 0.5x + x2 = 0 + -5.25

Combine like terms: 5.25 + -5.25 = 0.00
0.00 + 0.5x + x2 = 0 + -5.25
0.5x + x2 = 0 + -5.25

Combine like terms: 0 + -5.25 = -5.25
0.5x + x2 = -5.25

The x term is 0.5x.  Take half its coefficient (0.25).
Square it (0.0625) and add it to both sides.

Add '0.0625' to each side of the equation.
0.5x + 0.0625 + x2 = -5.25 + 0.0625

Reorder the terms:
0.0625 + 0.5x + x2 = -5.25 + 0.0625

Combine like terms: -5.25 + 0.0625 = -5.1875
0.0625 + 0.5x + x2 = -5.1875

Factor a perfect square on the left side:
(x + 0.25)(x + 0.25) = -5.1875

Can't calculate square root of the right side.

The solution to this equation could not be determined.

See similar equations:

| -15-x=23-2x | | -15-x=23-2g | | 4x(-1/20) | | 4x9-1/20) | | x+x+2+x+3=48 | | 4-(-1/20) | | 6-(-4/21) | | 2b-a=2(-3/8)-4/5 | | -3/4-(-5/16) | | 13/20-(-4/5) | | x^2+6x-y^2-4=0 | | 3x^2+6x-y^2-4=0 | | 11-z= | | (2x+1)-(3x-4)=0 | | x+16x=9 | | 13/20-(4/5) | | 36x-12xy= | | (2x+1)+(3x-4)=0 | | 2(y-4)=4y+6-4(-3y-1) | | (2x+1)+(3x-9)=0 | | (2x+4)+(3x-9)=0 | | 4(x-5)-4=-5(3x+2)-3x | | 3x^2+3y^2-6x+9y-6=0 | | 7v-5+2(3v+6)=-5(v+1) | | 3(y+4)=-4(2y-4)+y | | 4(u-1)=u+2-3(-5u-3) | | 3(y+7)=63 | | -3(-9w+7)-7w=2(w-7)-5 | | 4.3x-1.5+x-2.5= | | 4+2(4x-1)=-4(3x-1)+8x | | 4x/4-8/4=0 | | x=7+0 |

Equations solver categories