2x^2-6x+21=0

Simple and best practice solution for 2x^2-6x+21=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 2x^2-6x+21=0 equation:


Simplifying
2x2 + -6x + 21 = 0

Reorder the terms:
21 + -6x + 2x2 = 0

Solving
21 + -6x + 2x2 = 0

Solving for variable 'x'.

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

Divide each side by '2'.
10.5 + -3x + x2 = 0

Move the constant term to the right:

Add '-10.5' to each side of the equation.
10.5 + -3x + -10.5 + x2 = 0 + -10.5

Reorder the terms:
10.5 + -10.5 + -3x + x2 = 0 + -10.5

Combine like terms: 10.5 + -10.5 = 0.0
0.0 + -3x + x2 = 0 + -10.5
-3x + x2 = 0 + -10.5

Combine like terms: 0 + -10.5 = -10.5
-3x + x2 = -10.5

The x term is -3x.  Take half its coefficient (-1.5).
Square it (2.25) and add it to both sides.

Add '2.25' to each side of the equation.
-3x + 2.25 + x2 = -10.5 + 2.25

Reorder the terms:
2.25 + -3x + x2 = -10.5 + 2.25

Combine like terms: -10.5 + 2.25 = -8.25
2.25 + -3x + x2 = -8.25

Factor a perfect square on the left side:
(x + -1.5)(x + -1.5) = -8.25

Can't calculate square root of the right side.

The solution to this equation could not be determined.

See similar equations:

| 5(z-4)+6z-4= | | y^2-32= | | 6x+4x^2=5 | | A=rs+r | | 2x+4=122 | | y=3i | | 3D+8D=60 | | -6x-(9-x)-9= | | 10(z+4)-4(z+2)=3(z-1)+2(z-3) | | -7=8+x | | 5h+2(11-h)=(-5) | | -9+4y= | | r-8.3=-6.6 | | 4d-13+7d=(-24) | | 4z+2z=5z+5 | | 4x(x-6)=3(6-x) | | -5(z+7)=-4z-9 | | 6y+10-3y=9+2y-4 | | 7n-5=10+13 | | 8(x-6)-(4-9x)=16x | | 5x-5=10n+13 | | x^2-11x+5.25=0 | | 10x+7x=17x | | 2x+3y-100=0 | | 4x+27=3x+3y | | 7(x+8)+2(6x-7)=18(x+3)-5 | | 10x^2-34x+12=0 | | 10x+6-x=36 | | 3(q-2)=5q-7-2q | | 5(y-8)=9y-8 | | -3x^2y+12xy+36y=0 | | -3x^2y+12xy=36y |

Equations solver categories