9r^2+9r-9=0

Simple and best practice solution for 9r^2+9r-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 9r^2+9r-9=0 equation:


Simplifying
9r2 + 9r + -9 = 0

Reorder the terms:
-9 + 9r + 9r2 = 0

Solving
-9 + 9r + 9r2 = 0

Solving for variable 'r'.

Factor out the Greatest Common Factor (GCF), '9'.
9(-1 + r + r2) = 0

Ignore the factor 9.

Subproblem 1

Set the factor '(-1 + r + r2)' equal to zero and attempt to solve: Simplifying -1 + r + r2 = 0 Solving -1 + r + r2 = 0 Begin completing the square. Move the constant term to the right: Add '1' to each side of the equation. -1 + r + 1 + r2 = 0 + 1 Reorder the terms: -1 + 1 + r + r2 = 0 + 1 Combine like terms: -1 + 1 = 0 0 + r + r2 = 0 + 1 r + r2 = 0 + 1 Combine like terms: 0 + 1 = 1 r + r2 = 1 The r term is r. Take half its coefficient (0.5). Square it (0.25) and add it to both sides. Add '0.25' to each side of the equation. r + 0.25 + r2 = 1 + 0.25 Reorder the terms: 0.25 + r + r2 = 1 + 0.25 Combine like terms: 1 + 0.25 = 1.25 0.25 + r + r2 = 1.25 Factor a perfect square on the left side: (r + 0.5)(r + 0.5) = 1.25 Calculate the square root of the right side: 1.118033989 Break this problem into two subproblems by setting (r + 0.5) equal to 1.118033989 and -1.118033989.

Subproblem 1

r + 0.5 = 1.118033989 Simplifying r + 0.5 = 1.118033989 Reorder the terms: 0.5 + r = 1.118033989 Solving 0.5 + r = 1.118033989 Solving for variable 'r'. Move all terms containing r to the left, all other terms to the right. Add '-0.5' to each side of the equation. 0.5 + -0.5 + r = 1.118033989 + -0.5 Combine like terms: 0.5 + -0.5 = 0.0 0.0 + r = 1.118033989 + -0.5 r = 1.118033989 + -0.5 Combine like terms: 1.118033989 + -0.5 = 0.618033989 r = 0.618033989 Simplifying r = 0.618033989

Subproblem 2

r + 0.5 = -1.118033989 Simplifying r + 0.5 = -1.118033989 Reorder the terms: 0.5 + r = -1.118033989 Solving 0.5 + r = -1.118033989 Solving for variable 'r'. Move all terms containing r to the left, all other terms to the right. Add '-0.5' to each side of the equation. 0.5 + -0.5 + r = -1.118033989 + -0.5 Combine like terms: 0.5 + -0.5 = 0.0 0.0 + r = -1.118033989 + -0.5 r = -1.118033989 + -0.5 Combine like terms: -1.118033989 + -0.5 = -1.618033989 r = -1.618033989 Simplifying r = -1.618033989

Solution

The solution to the problem is based on the solutions from the subproblems. r = {0.618033989, -1.618033989}

Solution

r = {0.618033989, -1.618033989}

See similar equations:

| 13x-10=12x+6 | | 2x-4/2=12 | | x^2(25x-242)=642 | | x-8+7=2 | | x=6(x-1) | | 40+6x=2x | | (x-3)(x-3+2x+9)=9(9+3x+2) | | x^2+35x-2=0 | | 3+15t-5t^2=11 | | 10-g/-12=7 | | Y=30x+8 | | 3x^2-30x-40=0 | | N-7/2=7 | | 4x+3=8+2x | | x+(x+50)=500 | | -5z+6=-4 | | 8x+5+4=6x+2x+9 | | -476=7(-7x+9) | | 14p=98 | | 5y/63-4/9 | | 6x-127=-x+76 | | t-25=30 | | 9=2-11y | | 2x-7=10x-39 | | 8x-125=-5x+109 | | m(m-5)+14=m(m+2)-14 | | 8x^2-x^4=0 | | 10x-2x=7 | | 31/4x1/6x2/3 | | 0.12y-1=0.095y-0.9 | | x^2-20x-51=0 | | -151-5x=57+11x |

Equations solver categories