3x^2+8x=-15

Simple and best practice solution for 3x^2+8x=-15 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 3x^2+8x=-15 equation:


Simplifying
3x2 + 8x = -15

Reorder the terms:
8x + 3x2 = -15

Solving
8x + 3x2 = -15

Solving for variable 'x'.

Reorder the terms:
15 + 8x + 3x2 = -15 + 15

Combine like terms: -15 + 15 = 0
15 + 8x + 3x2 = 0

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

Divide each side by '3'.
5 + 2.666666667x + x2 = 0

Move the constant term to the right:

Add '-5' to each side of the equation.
5 + 2.666666667x + -5 + x2 = 0 + -5

Reorder the terms:
5 + -5 + 2.666666667x + x2 = 0 + -5

Combine like terms: 5 + -5 = 0
0 + 2.666666667x + x2 = 0 + -5
2.666666667x + x2 = 0 + -5

Combine like terms: 0 + -5 = -5
2.666666667x + x2 = -5

The x term is 2.666666667x.  Take half its coefficient (1.333333334).
Square it (1.777777780) and add it to both sides.

Add '1.777777780' to each side of the equation.
2.666666667x + 1.777777780 + x2 = -5 + 1.777777780

Reorder the terms:
1.777777780 + 2.666666667x + x2 = -5 + 1.777777780

Combine like terms: -5 + 1.777777780 = -3.22222222
1.777777780 + 2.666666667x + x2 = -3.22222222

Factor a perfect square on the left side:
(x + 1.333333334)(x + 1.333333334) = -3.22222222

Can't calculate square root of the right side.

The solution to this equation could not be determined.

See similar equations:

| 24-3x=17+2x | | 3/5*2/7*1/3= | | 75=2x+3 | | 12t+9=5t | | 2(6x-9)=-12x-18 | | 72+28x-4x^2=0 | | 11x+6=14x+9 | | 3y-8+28=180 | | 140/5=x | | 3x+2(x+5)=17 | | 7-3f/4=2 | | 3z+2z-20=15 | | 2x^3-6x=3-x^2 | | 3y-8=180 | | 3y-8=360 | | 5z-z+8=18 | | -4x-2=-7x-11 | | 3a-a+8=-16 | | -3(x-2)=-2(x-5) | | 6/20= | | tan(x)=0.03 | | 3x^2-32x+63=0 | | 0=18x-36 | | 8x-2=5x+18 | | 3x^2-12x-17=0 | | -x^2-36-12x=0 | | 20=8+6a | | 8*40-19/-7/7= | | 2x+x+6+90=180 | | 5x-30/8=-2x | | 3/2x=1/x-5 | | n^3+2n^2+5n+10= |

Equations solver categories