40=b(b+4)

Simple and best practice solution for 40=b(b+4) 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 40=b(b+4) equation:


Simplifying
40 = b(b + 4)

Reorder the terms:
40 = b(4 + b)
40 = (4 * b + b * b)
40 = (4b + b2)

Solving
40 = 4b + b2

Solving for variable 'b'.

Reorder the terms:
40 + -4b + -1b2 = 4b + -4b + b2 + -1b2

Combine like terms: 4b + -4b = 0
40 + -4b + -1b2 = 0 + b2 + -1b2
40 + -4b + -1b2 = b2 + -1b2

Combine like terms: b2 + -1b2 = 0
40 + -4b + -1b2 = 0

Begin completing the square.  Divide all terms by
-1 the coefficient of the squared term: 

Divide each side by '-1'.
-40 + 4b + b2 = 0

Move the constant term to the right:

Add '40' to each side of the equation.
-40 + 4b + 40 + b2 = 0 + 40

Reorder the terms:
-40 + 40 + 4b + b2 = 0 + 40

Combine like terms: -40 + 40 = 0
0 + 4b + b2 = 0 + 40
4b + b2 = 0 + 40

Combine like terms: 0 + 40 = 40
4b + b2 = 40

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

Add '4' to each side of the equation.
4b + 4 + b2 = 40 + 4

Reorder the terms:
4 + 4b + b2 = 40 + 4

Combine like terms: 40 + 4 = 44
4 + 4b + b2 = 44

Factor a perfect square on the left side:
(b + 2)(b + 2) = 44

Calculate the square root of the right side: 6.633249581

Break this problem into two subproblems by setting 
(b + 2) equal to 6.633249581 and -6.633249581.

Subproblem 1

b + 2 = 6.633249581 Simplifying b + 2 = 6.633249581 Reorder the terms: 2 + b = 6.633249581 Solving 2 + b = 6.633249581 Solving for variable 'b'. Move all terms containing b to the left, all other terms to the right. Add '-2' to each side of the equation. 2 + -2 + b = 6.633249581 + -2 Combine like terms: 2 + -2 = 0 0 + b = 6.633249581 + -2 b = 6.633249581 + -2 Combine like terms: 6.633249581 + -2 = 4.633249581 b = 4.633249581 Simplifying b = 4.633249581

Subproblem 2

b + 2 = -6.633249581 Simplifying b + 2 = -6.633249581 Reorder the terms: 2 + b = -6.633249581 Solving 2 + b = -6.633249581 Solving for variable 'b'. Move all terms containing b to the left, all other terms to the right. Add '-2' to each side of the equation. 2 + -2 + b = -6.633249581 + -2 Combine like terms: 2 + -2 = 0 0 + b = -6.633249581 + -2 b = -6.633249581 + -2 Combine like terms: -6.633249581 + -2 = -8.633249581 b = -8.633249581 Simplifying b = -8.633249581

Solution

The solution to the problem is based on the solutions from the subproblems. b = {4.633249581, -8.633249581}

See similar equations:

| 2x=24-24 | | 54t^2-9t-30=0 | | (m^3)-(n^3)=0 | | 13+2x= | | 11.3=8.3+0.6 | | 3a^2b+2a^2b^2+(-ab^2+a^2b^2)= | | x+2x-1-1=x | | 49s^2+28s=4 | | 105=2(164+x) | | 9+4x^2+x^4=13 | | 2y=0-3x | | y^2+y+20=0 | | log(5)(-8-4x)=1 | | h^2+6h-21=0 | | 27 x+29=38 | | 50+3n=c | | 6.1=-Log(x) | | -2/3-5/6 | | 41x^2-13x=7x-9x^2 | | 6y-5= | | 0.1+0.1+0.05= | | 3a^2b+2a^2b^2+-ab^2+a^2b^2= | | 16x+44-3x=239 | | 8x-1/2-2x=3 | | 9=4-3 | | 9x-5x-2=-2 | | 7m-8.5=19.5 | | -33=3(x-1) | | 18k-3=27+3h | | 34=4w-2 | | 18k-3=27+3 | | -20+-1x+x^2=0 |

Equations solver categories