8c^2-30c=-9

Simple and best practice solution for 8c^2-30c=-9 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 8c^2-30c=-9 equation:


Simplifying
8c2 + -30c = -9

Reorder the terms:
-30c + 8c2 = -9

Solving
-30c + 8c2 = -9

Solving for variable 'c'.

Reorder the terms:
9 + -30c + 8c2 = -9 + 9

Combine like terms: -9 + 9 = 0
9 + -30c + 8c2 = 0

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

Divide each side by '8'.
1.125 + -3.75c + c2 = 0

Move the constant term to the right:

Add '-1.125' to each side of the equation.
1.125 + -3.75c + -1.125 + c2 = 0 + -1.125

Reorder the terms:
1.125 + -1.125 + -3.75c + c2 = 0 + -1.125

Combine like terms: 1.125 + -1.125 = 0.000
0.000 + -3.75c + c2 = 0 + -1.125
-3.75c + c2 = 0 + -1.125

Combine like terms: 0 + -1.125 = -1.125
-3.75c + c2 = -1.125

The c term is -3.75c.  Take half its coefficient (-1.875).
Square it (3.515625) and add it to both sides.

Add '3.515625' to each side of the equation.
-3.75c + 3.515625 + c2 = -1.125 + 3.515625

Reorder the terms:
3.515625 + -3.75c + c2 = -1.125 + 3.515625

Combine like terms: -1.125 + 3.515625 = 2.390625
3.515625 + -3.75c + c2 = 2.390625

Factor a perfect square on the left side:
(c + -1.875)(c + -1.875) = 2.390625

Calculate the square root of the right side: 1.54616461

Break this problem into two subproblems by setting 
(c + -1.875) equal to 1.54616461 and -1.54616461.

Subproblem 1

c + -1.875 = 1.54616461 Simplifying c + -1.875 = 1.54616461 Reorder the terms: -1.875 + c = 1.54616461 Solving -1.875 + c = 1.54616461 Solving for variable 'c'. Move all terms containing c to the left, all other terms to the right. Add '1.875' to each side of the equation. -1.875 + 1.875 + c = 1.54616461 + 1.875 Combine like terms: -1.875 + 1.875 = 0.000 0.000 + c = 1.54616461 + 1.875 c = 1.54616461 + 1.875 Combine like terms: 1.54616461 + 1.875 = 3.42116461 c = 3.42116461 Simplifying c = 3.42116461

Subproblem 2

c + -1.875 = -1.54616461 Simplifying c + -1.875 = -1.54616461 Reorder the terms: -1.875 + c = -1.54616461 Solving -1.875 + c = -1.54616461 Solving for variable 'c'. Move all terms containing c to the left, all other terms to the right. Add '1.875' to each side of the equation. -1.875 + 1.875 + c = -1.54616461 + 1.875 Combine like terms: -1.875 + 1.875 = 0.000 0.000 + c = -1.54616461 + 1.875 c = -1.54616461 + 1.875 Combine like terms: -1.54616461 + 1.875 = 0.32883539 c = 0.32883539 Simplifying c = 0.32883539

Solution

The solution to the problem is based on the solutions from the subproblems. c = {3.42116461, 0.32883539}

See similar equations:

| y=(-6a+4x)/2 | | (-6a+4x)/2=y | | -3y+2+3y=1 | | 0.21y-0.8=0.11y-0.8y | | 4(7-x)=x/3 | | .12(x-6)=2(x-9) | | 12*x=7*x+30 | | 4(x+8)=48 | | 41=-2x+6x+5 | | 8r+4=19+2r | | .9(x-6)=8(x+6) | | 5t-2(t+2)=-(2t+15) | | 3x+4/5-4x+3/5 | | 38-3x=7x+8 | | -5(x+3)-44=1-20 | | (6y-10)(6y+10)= | | 7x+2=6(x-4)+8 | | 12y=11(y+9) | | 21v^2+184v=-75 | | 10x+100(97-x)=5830 | | 7x-3x+2=5-2x+9 | | -2x-2x=14-6 | | B-3+7b=32 | | X^2-9x=4/243 | | 18-5y=7 | | 6y+5=5y-8 | | -7x+8+4x=-16 | | 4x+11=-9 | | 21j+9j-10=-277 | | X^2-9x=243/4 | | 0.1x=8 | | 3n-6=6+7n |

Equations solver categories