3r(r+4)+5(2r+6)=

Simple and best practice solution for 3r(r+4)+5(2r+6)= 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 3r(r+4)+5(2r+6)= equation:


Simplifying
3r(r + 4) + 5(2r + 6) = 0

Reorder the terms:
3r(4 + r) + 5(2r + 6) = 0
(4 * 3r + r * 3r) + 5(2r + 6) = 0
(12r + 3r2) + 5(2r + 6) = 0

Reorder the terms:
12r + 3r2 + 5(6 + 2r) = 0
12r + 3r2 + (6 * 5 + 2r * 5) = 0
12r + 3r2 + (30 + 10r) = 0

Reorder the terms:
30 + 12r + 10r + 3r2 = 0

Combine like terms: 12r + 10r = 22r
30 + 22r + 3r2 = 0

Solving
30 + 22r + 3r2 = 0

Solving for variable 'r'.

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

Divide each side by '3'.
10 + 7.333333333r + r2 = 0

Move the constant term to the right:

Add '-10' to each side of the equation.
10 + 7.333333333r + -10 + r2 = 0 + -10

Reorder the terms:
10 + -10 + 7.333333333r + r2 = 0 + -10

Combine like terms: 10 + -10 = 0
0 + 7.333333333r + r2 = 0 + -10
7.333333333r + r2 = 0 + -10

Combine like terms: 0 + -10 = -10
7.333333333r + r2 = -10

The r term is 7.333333333r.  Take half its coefficient (3.666666667).
Square it (13.44444445) and add it to both sides.

Add '13.44444445' to each side of the equation.
7.333333333r + 13.44444445 + r2 = -10 + 13.44444445

Reorder the terms:
13.44444445 + 7.333333333r + r2 = -10 + 13.44444445

Combine like terms: -10 + 13.44444445 = 3.44444445
13.44444445 + 7.333333333r + r2 = 3.44444445

Factor a perfect square on the left side:
(r + 3.666666667)(r + 3.666666667) = 3.44444445

Calculate the square root of the right side: 1.855921456

Break this problem into two subproblems by setting 
(r + 3.666666667) equal to 1.855921456 and -1.855921456.

Subproblem 1

r + 3.666666667 = 1.855921456 Simplifying r + 3.666666667 = 1.855921456 Reorder the terms: 3.666666667 + r = 1.855921456 Solving 3.666666667 + r = 1.855921456 Solving for variable 'r'. Move all terms containing r to the left, all other terms to the right. Add '-3.666666667' to each side of the equation. 3.666666667 + -3.666666667 + r = 1.855921456 + -3.666666667 Combine like terms: 3.666666667 + -3.666666667 = 0.000000000 0.000000000 + r = 1.855921456 + -3.666666667 r = 1.855921456 + -3.666666667 Combine like terms: 1.855921456 + -3.666666667 = -1.810745211 r = -1.810745211 Simplifying r = -1.810745211

Subproblem 2

r + 3.666666667 = -1.855921456 Simplifying r + 3.666666667 = -1.855921456 Reorder the terms: 3.666666667 + r = -1.855921456 Solving 3.666666667 + r = -1.855921456 Solving for variable 'r'. Move all terms containing r to the left, all other terms to the right. Add '-3.666666667' to each side of the equation. 3.666666667 + -3.666666667 + r = -1.855921456 + -3.666666667 Combine like terms: 3.666666667 + -3.666666667 = 0.000000000 0.000000000 + r = -1.855921456 + -3.666666667 r = -1.855921456 + -3.666666667 Combine like terms: -1.855921456 + -3.666666667 = -5.522588123 r = -5.522588123 Simplifying r = -5.522588123

Solution

The solution to the problem is based on the solutions from the subproblems. r = {-1.810745211, -5.522588123}

See similar equations:

| 134-29= | | -x^2+70x-600=0 | | 6(x-4)+7=-15 | | 3x+1=-4x-83 | | 2+56789=56 | | 3r(r+4)+5(r+6)= | | k^2-4k+3=0 | | -100=12+9 | | -10-18(19+11r)= | | (16/2)^2 | | 6+v/-8=4/4 | | n^2=-5n+24 | | 29+x=8 | | -6m=4(m-12) | | (16/2^2)+8*2^3-(1/2)(3^2*4-25)^2 | | m^2=-m | | 2x^2+18x=-2 | | -2f+18-4d=60 | | v^2-12v=-35 | | 729*(1/3)^9 | | L=(P-2W)/2 | | L=2(W-2P) | | x^2=-2x+15 | | 16/2^2+8x2^3-1/2(3^2*4-25)^2 | | x+y+6z=-30 | | L=2/(P-W) | | a^2-6=a | | 6/5(x-4)=5/2(x-6)+5 | | 2.7a=8.37 | | 10b-5b^2/b^2+3b-10 | | 2.7a=8.73 | | 11(-12z+16)= |

Equations solver categories