5x^2+30x-7=21

Simple and best practice solution for 5x^2+30x-7=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 5x^2+30x-7=21 equation:


Simplifying
5x2 + 30x + -7 = 21

Reorder the terms:
-7 + 30x + 5x2 = 21

Solving
-7 + 30x + 5x2 = 21

Solving for variable 'x'.

Reorder the terms:
-7 + -21 + 30x + 5x2 = 21 + -21

Combine like terms: -7 + -21 = -28
-28 + 30x + 5x2 = 21 + -21

Combine like terms: 21 + -21 = 0
-28 + 30x + 5x2 = 0

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

Divide each side by '5'.
-5.6 + 6x + x2 = 0

Move the constant term to the right:

Add '5.6' to each side of the equation.
-5.6 + 6x + 5.6 + x2 = 0 + 5.6

Reorder the terms:
-5.6 + 5.6 + 6x + x2 = 0 + 5.6

Combine like terms: -5.6 + 5.6 = 0.0
0.0 + 6x + x2 = 0 + 5.6
6x + x2 = 0 + 5.6

Combine like terms: 0 + 5.6 = 5.6
6x + x2 = 5.6

The x term is 6x.  Take half its coefficient (3).
Square it (9) and add it to both sides.

Add '9' to each side of the equation.
6x + 9 + x2 = 5.6 + 9

Reorder the terms:
9 + 6x + x2 = 5.6 + 9

Combine like terms: 5.6 + 9 = 14.6
9 + 6x + x2 = 14.6

Factor a perfect square on the left side:
(x + 3)(x + 3) = 14.6

Calculate the square root of the right side: 3.820994635

Break this problem into two subproblems by setting 
(x + 3) equal to 3.820994635 and -3.820994635.

Subproblem 1

x + 3 = 3.820994635 Simplifying x + 3 = 3.820994635 Reorder the terms: 3 + x = 3.820994635 Solving 3 + x = 3.820994635 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-3' to each side of the equation. 3 + -3 + x = 3.820994635 + -3 Combine like terms: 3 + -3 = 0 0 + x = 3.820994635 + -3 x = 3.820994635 + -3 Combine like terms: 3.820994635 + -3 = 0.820994635 x = 0.820994635 Simplifying x = 0.820994635

Subproblem 2

x + 3 = -3.820994635 Simplifying x + 3 = -3.820994635 Reorder the terms: 3 + x = -3.820994635 Solving 3 + x = -3.820994635 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-3' to each side of the equation. 3 + -3 + x = -3.820994635 + -3 Combine like terms: 3 + -3 = 0 0 + x = -3.820994635 + -3 x = -3.820994635 + -3 Combine like terms: -3.820994635 + -3 = -6.820994635 x = -6.820994635 Simplifying x = -6.820994635

Solution

The solution to the problem is based on the solutions from the subproblems. x = {0.820994635, -6.820994635}

See similar equations:

| -3y+8(y-5)=5 | | p=1x+y | | p+x=y | | 17+3x-5= | | -5+y=-4 | | 8u-11=6u-5 | | (28b-5)-9(3b+2)=-3 | | x+0=-4 | | s+7(3/5)=(-1/2) | | 63/8-46/7 | | 380x^18+12=0 | | 3x^2-23x=8 | | 3x-5(x+4)=2(x-7) | | x+20+2x+x=180 | | -6(4b+1)+(25b-2)=0 | | 3x/8+17=20 | | 7x/2-10 | | 3x-2x=-4x+-4 | | (7x-2y)-(4x-9y)= | | (6y+4)+(7-3)= | | 5x+2-3x+3= | | 9x+5=5x-11 | | 3x/5-4=5 | | -p/12=6 | | -9/12=6 | | 2/9x-4-2/3 | | 125/25 | | 8(6y-8)-(7y+8)= | | (36+4)/8=x | | (9k/15+18/15)*(10k/15+20/15) | | 12/5f=18 | | 7-2(y+5)=4(1-3y) |

Equations solver categories