y^2+3y=9

Simple and best practice solution for y^2+3y=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 y^2+3y=9 equation:


Simplifying
y2 + 3y = 9

Reorder the terms:
3y + y2 = 9

Solving
3y + y2 = 9

Solving for variable 'y'.

Reorder the terms:
-9 + 3y + y2 = 9 + -9

Combine like terms: 9 + -9 = 0
-9 + 3y + y2 = 0

Begin completing the square.

Move the constant term to the right:

Add '9' to each side of the equation.
-9 + 3y + 9 + y2 = 0 + 9

Reorder the terms:
-9 + 9 + 3y + y2 = 0 + 9

Combine like terms: -9 + 9 = 0
0 + 3y + y2 = 0 + 9
3y + y2 = 0 + 9

Combine like terms: 0 + 9 = 9
3y + y2 = 9

The y term is 3y.  Take half its coefficient (1.5).
Square it (2.25) and add it to both sides.

Add '2.25' to each side of the equation.
3y + 2.25 + y2 = 9 + 2.25

Reorder the terms:
2.25 + 3y + y2 = 9 + 2.25

Combine like terms: 9 + 2.25 = 11.25
2.25 + 3y + y2 = 11.25

Factor a perfect square on the left side:
(y + 1.5)(y + 1.5) = 11.25

Calculate the square root of the right side: 3.354101966

Break this problem into two subproblems by setting 
(y + 1.5) equal to 3.354101966 and -3.354101966.

Subproblem 1

y + 1.5 = 3.354101966 Simplifying y + 1.5 = 3.354101966 Reorder the terms: 1.5 + y = 3.354101966 Solving 1.5 + y = 3.354101966 Solving for variable 'y'. Move all terms containing y to the left, all other terms to the right. Add '-1.5' to each side of the equation. 1.5 + -1.5 + y = 3.354101966 + -1.5 Combine like terms: 1.5 + -1.5 = 0.0 0.0 + y = 3.354101966 + -1.5 y = 3.354101966 + -1.5 Combine like terms: 3.354101966 + -1.5 = 1.854101966 y = 1.854101966 Simplifying y = 1.854101966

Subproblem 2

y + 1.5 = -3.354101966 Simplifying y + 1.5 = -3.354101966 Reorder the terms: 1.5 + y = -3.354101966 Solving 1.5 + y = -3.354101966 Solving for variable 'y'. Move all terms containing y to the left, all other terms to the right. Add '-1.5' to each side of the equation. 1.5 + -1.5 + y = -3.354101966 + -1.5 Combine like terms: 1.5 + -1.5 = 0.0 0.0 + y = -3.354101966 + -1.5 y = -3.354101966 + -1.5 Combine like terms: -3.354101966 + -1.5 = -4.854101966 y = -4.854101966 Simplifying y = -4.854101966

Solution

The solution to the problem is based on the solutions from the subproblems. y = {1.854101966, -4.854101966}

See similar equations:

| -7/2(y-6)-1/4y | | 7x-4y=16 | | 3(k-5)+1=10 | | 4(p+2)-8=4 | | n/7=n/3+4/21 | | -3(p+-1)=-6 | | 1/u-2 | | 3(8y+5)-2(2y)=57 | | 3x+5=0-20 | | 20=4(q+2) | | r^2-r-1=0 | | 3/u+2 | | 11=0-3-10 | | 3(k+20)-6=12 | | 9x^2+6xy+y^2-64x-8y+140=0 | | a+11=17 | | -11=-3u | | 3(4k+2)-17k+8+4= | | 3=-12/f | | 3=9/y | | -5.3(4s+6)-1.6(2s-5)= | | 3(s+1)+6=6 | | 5X=8X+15 | | 3(m+2)=9 | | 6t^2-t-1/3(t^2+1)=2 | | (x+8)(x-8)=y | | c-8c= | | 10=6t^2+7t | | 12x+24=108 | | -6.4(2y+5)-2.3(3y-6)= | | 80x-4x^2=0 | | 100*-13= |

Equations solver categories