y^2+4y-9=0

Simple and best practice solution for y^2+4y-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 y^2+4y-9=0 equation:


Simplifying
y2 + 4y + -9 = 0

Reorder the terms:
-9 + 4y + y2 = 0

Solving
-9 + 4y + y2 = 0

Solving for variable 'y'.

Begin completing the square.

Move the constant term to the right:

Add '9' to each side of the equation.
-9 + 4y + 9 + y2 = 0 + 9

Reorder the terms:
-9 + 9 + 4y + y2 = 0 + 9

Combine like terms: -9 + 9 = 0
0 + 4y + y2 = 0 + 9
4y + y2 = 0 + 9

Combine like terms: 0 + 9 = 9
4y + y2 = 9

The y term is 4y.  Take half its coefficient (2).
Square it (4) and add it to both sides.

Add '4' to each side of the equation.
4y + 4 + y2 = 9 + 4

Reorder the terms:
4 + 4y + y2 = 9 + 4

Combine like terms: 9 + 4 = 13
4 + 4y + y2 = 13

Factor a perfect square on the left side:
(y + 2)(y + 2) = 13

Calculate the square root of the right side: 3.605551275

Break this problem into two subproblems by setting 
(y + 2) equal to 3.605551275 and -3.605551275.

Subproblem 1

y + 2 = 3.605551275 Simplifying y + 2 = 3.605551275 Reorder the terms: 2 + y = 3.605551275 Solving 2 + y = 3.605551275 Solving for variable 'y'. Move all terms containing y to the left, all other terms to the right. Add '-2' to each side of the equation. 2 + -2 + y = 3.605551275 + -2 Combine like terms: 2 + -2 = 0 0 + y = 3.605551275 + -2 y = 3.605551275 + -2 Combine like terms: 3.605551275 + -2 = 1.605551275 y = 1.605551275 Simplifying y = 1.605551275

Subproblem 2

y + 2 = -3.605551275 Simplifying y + 2 = -3.605551275 Reorder the terms: 2 + y = -3.605551275 Solving 2 + y = -3.605551275 Solving for variable 'y'. Move all terms containing y to the left, all other terms to the right. Add '-2' to each side of the equation. 2 + -2 + y = -3.605551275 + -2 Combine like terms: 2 + -2 = 0 0 + y = -3.605551275 + -2 y = -3.605551275 + -2 Combine like terms: -3.605551275 + -2 = -5.605551275 y = -5.605551275 Simplifying y = -5.605551275

Solution

The solution to the problem is based on the solutions from the subproblems. y = {1.605551275, -5.605551275}

See similar equations:

| 2x+59=6x-5 | | -3.8+t=-6.6 | | x^3-9x^2-214x+936=0 | | 5u^2-35uv+60v^2=0 | | 7x-1+2=0 | | x-.20x=44 | | 2x+6=2x-6 | | x^5+3x^4-4x^3-12x^2=0 | | x-0.25x=42 | | 75x-2=11 | | a^2+9ab=0 | | 100+25x=475 | | x^3-11x^2-174x+1224=0 | | g(x)=-2x^2+5x-3 | | 6-7(m-3)=-2 | | 15x+2=27 | | w^2-6w+6=0 | | 5m^4+5m^3-30m^2=0 | | x-(-25)=24 | | -3.4+r=-9.5 | | 15-(2m+5)=5+2m-11 | | 35+3y-7=12y-14-2y | | 15+8=23 | | C=2m+4d | | n+3.2=8.4 | | 4x-1-3x+3=16 | | 3n^2+18n^2+24n=0 | | n^2(n-7)(n+7)=0 | | 3x+15-8x=15 | | 3n^2+18n^2+24n= | | 35+95+(H+-5)=35 | | 2x^2+9=137 |

Equations solver categories