15x^2-74x-9=0

Simple and best practice solution for 15x^2-74x-9=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 15x^2-74x-9=0 equation:


Simplifying
15x2 + -74x + -9 = 0

Reorder the terms:
-9 + -74x + 15x2 = 0

Solving
-9 + -74x + 15x2 = 0

Solving for variable 'x'.

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

Divide each side by '15'.
-0.6 + -4.933333333x + x2 = 0

Move the constant term to the right:

Add '0.6' to each side of the equation.
-0.6 + -4.933333333x + 0.6 + x2 = 0 + 0.6

Reorder the terms:
-0.6 + 0.6 + -4.933333333x + x2 = 0 + 0.6

Combine like terms: -0.6 + 0.6 = 0.0
0.0 + -4.933333333x + x2 = 0 + 0.6
-4.933333333x + x2 = 0 + 0.6

Combine like terms: 0 + 0.6 = 0.6
-4.933333333x + x2 = 0.6

The x term is -4.933333333x.  Take half its coefficient (-2.466666667).
Square it (6.084444446) and add it to both sides.

Add '6.084444446' to each side of the equation.
-4.933333333x + 6.084444446 + x2 = 0.6 + 6.084444446

Reorder the terms:
6.084444446 + -4.933333333x + x2 = 0.6 + 6.084444446

Combine like terms: 0.6 + 6.084444446 = 6.684444446
6.084444446 + -4.933333333x + x2 = 6.684444446

Factor a perfect square on the left side:
(x + -2.466666667)(x + -2.466666667) = 6.684444446

Calculate the square root of the right side: 2.585429258

Break this problem into two subproblems by setting 
(x + -2.466666667) equal to 2.585429258 and -2.585429258.

Subproblem 1

x + -2.466666667 = 2.585429258 Simplifying x + -2.466666667 = 2.585429258 Reorder the terms: -2.466666667 + x = 2.585429258 Solving -2.466666667 + x = 2.585429258 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '2.466666667' to each side of the equation. -2.466666667 + 2.466666667 + x = 2.585429258 + 2.466666667 Combine like terms: -2.466666667 + 2.466666667 = 0.000000000 0.000000000 + x = 2.585429258 + 2.466666667 x = 2.585429258 + 2.466666667 Combine like terms: 2.585429258 + 2.466666667 = 5.052095925 x = 5.052095925 Simplifying x = 5.052095925

Subproblem 2

x + -2.466666667 = -2.585429258 Simplifying x + -2.466666667 = -2.585429258 Reorder the terms: -2.466666667 + x = -2.585429258 Solving -2.466666667 + x = -2.585429258 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '2.466666667' to each side of the equation. -2.466666667 + 2.466666667 + x = -2.585429258 + 2.466666667 Combine like terms: -2.466666667 + 2.466666667 = 0.000000000 0.000000000 + x = -2.585429258 + 2.466666667 x = -2.585429258 + 2.466666667 Combine like terms: -2.585429258 + 2.466666667 = -0.118762591 x = -0.118762591 Simplifying x = -0.118762591

Solution

The solution to the problem is based on the solutions from the subproblems. x = {5.052095925, -0.118762591}

See similar equations:

| 2y=9x-6 | | 6(8y+4)=-31+7y | | x=-0.4x^2+80x-1600 | | 3x^2-2x^3=.95 | | 2x-8+6x=8x+0-4x | | 9x-2=-6x+5 | | 2x-8+6x=8x+0-4c | | (1/2)*4x^2+4x+5 | | 2x-5=6x+2 | | 4x+(7/x)=29 | | 9y-4=36+y | | 2x+3x+6+2x-3+x+7+2x+10=360 | | 1/2*4x^2+4x+5 | | 3J+2S=81.35 | | 5x+6=9x-1 | | 2x-6+9=5x-5+8 | | 40+80=0 | | 2l*w=48 | | 777-34y= | | 14.95(7-c)+16.88c=106.58 | | 2v-1+7(2v+1)=-2(v+5) | | 13x+50000=18x | | 14.95(7-c)+16.88c=116.23 | | 14.95*(7-c)+16.88c=116.23 | | (7x+4)-(2x+9)= | | 14.95a+16.88b=80.54 | | 4x^2-5x+7=7 | | 2x+44=90 | | P*v/t=r | | -3x+4/9-2x-1/3=4/9 | | 3xy=56 | | -3x+3=15 |

Equations solver categories