9x^2+15x+c=20+c

Simple and best practice solution for 9x^2+15x+c=20+c 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 9x^2+15x+c=20+c equation:


Simplifying
9x2 + 15x + c = 20 + c

Reorder the terms:
c + 15x + 9x2 = 20 + c

Add '-1c' to each side of the equation.
c + 15x + -1c + 9x2 = 20 + c + -1c

Reorder the terms:
c + -1c + 15x + 9x2 = 20 + c + -1c

Combine like terms: c + -1c = 0
0 + 15x + 9x2 = 20 + c + -1c
15x + 9x2 = 20 + c + -1c

Combine like terms: c + -1c = 0
15x + 9x2 = 20 + 0
15x + 9x2 = 20

Solving
15x + 9x2 = 20

Solving for variable 'x'.

Reorder the terms:
-20 + 15x + 9x2 = 20 + -20

Combine like terms: 20 + -20 = 0
-20 + 15x + 9x2 = 0

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

Divide each side by '9'.
-2.222222222 + 1.666666667x + x2 = 0

Move the constant term to the right:

Add '2.222222222' to each side of the equation.
-2.222222222 + 1.666666667x + 2.222222222 + x2 = 0 + 2.222222222

Reorder the terms:
-2.222222222 + 2.222222222 + 1.666666667x + x2 = 0 + 2.222222222

Combine like terms: -2.222222222 + 2.222222222 = 0.000000000
0.000000000 + 1.666666667x + x2 = 0 + 2.222222222
1.666666667x + x2 = 0 + 2.222222222

Combine like terms: 0 + 2.222222222 = 2.222222222
1.666666667x + x2 = 2.222222222

The x term is 1.666666667x.  Take half its coefficient (0.8333333335).
Square it (0.6944444447) and add it to both sides.

Add '0.6944444447' to each side of the equation.
1.666666667x + 0.6944444447 + x2 = 2.222222222 + 0.6944444447

Reorder the terms:
0.6944444447 + 1.666666667x + x2 = 2.222222222 + 0.6944444447

Combine like terms: 2.222222222 + 0.6944444447 = 2.9166666667
0.6944444447 + 1.666666667x + x2 = 2.9166666667

Factor a perfect square on the left side:
(x + 0.8333333335)(x + 0.8333333335) = 2.9166666667

Calculate the square root of the right side: 1.707825128

Break this problem into two subproblems by setting 
(x + 0.8333333335) equal to 1.707825128 and -1.707825128.

Subproblem 1

x + 0.8333333335 = 1.707825128 Simplifying x + 0.8333333335 = 1.707825128 Reorder the terms: 0.8333333335 + x = 1.707825128 Solving 0.8333333335 + x = 1.707825128 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-0.8333333335' to each side of the equation. 0.8333333335 + -0.8333333335 + x = 1.707825128 + -0.8333333335 Combine like terms: 0.8333333335 + -0.8333333335 = 0.0000000000 0.0000000000 + x = 1.707825128 + -0.8333333335 x = 1.707825128 + -0.8333333335 Combine like terms: 1.707825128 + -0.8333333335 = 0.8744917945 x = 0.8744917945 Simplifying x = 0.8744917945

Subproblem 2

x + 0.8333333335 = -1.707825128 Simplifying x + 0.8333333335 = -1.707825128 Reorder the terms: 0.8333333335 + x = -1.707825128 Solving 0.8333333335 + x = -1.707825128 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-0.8333333335' to each side of the equation. 0.8333333335 + -0.8333333335 + x = -1.707825128 + -0.8333333335 Combine like terms: 0.8333333335 + -0.8333333335 = 0.0000000000 0.0000000000 + x = -1.707825128 + -0.8333333335 x = -1.707825128 + -0.8333333335 Combine like terms: -1.707825128 + -0.8333333335 = -2.5411584615 x = -2.5411584615 Simplifying x = -2.5411584615

Solution

The solution to the problem is based on the solutions from the subproblems. x = {0.8744917945, -2.5411584615}

See similar equations:

| ((x^3)+(2x))=(16) | | f(x)=(x^2)-3x-5 | | X+3.75=11.25 | | 25y+2y+16y+36y+1+y= | | X-6=20/5 | | 6x-5=8x+15 | | x=ln(2y+1) | | 7(4s+8)=196 | | X-0.0275X=10 | | 0.5x^2+0.5x^2+x+2=0 | | f^-1(x)=(cosx)/((x^1/3)^1/2) | | -7x-3x=22-22 | | 3x+3y=-4 | | x^4+x^3+x^2-3x=0 | | -3(t+5)+(4t+3)=8 | | 17x+12=9x+52 | | X-2.75/100=10 | | x*2+x*0.8=5000 | | 2n+7-n-2=0 | | 20x+30=18x+50 | | 20x-30=-18x-50 | | 7n-4n+2+3=20 | | 4(x+5)=2(x-4) | | z^2+11z-10=0 | | 5-3x=x-23 | | 7-a=5 | | 11+1+2x=x | | x-2x-1=11 | | 3x+4=25-4x | | (m-1)x^2+2mx+m+1=0 | | 420/x*11-66=600 | | 78.88+x=647.13 |

Equations solver categories