3r^2=13r+4

Simple and best practice solution for 3r^2=13r+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 3r^2=13r+4 equation:


Simplifying
3r2 = 13r + 4

Reorder the terms:
3r2 = 4 + 13r

Solving
3r2 = 4 + 13r

Solving for variable 'r'.

Reorder the terms:
-4 + -13r + 3r2 = 4 + 13r + -4 + -13r

Reorder the terms:
-4 + -13r + 3r2 = 4 + -4 + 13r + -13r

Combine like terms: 4 + -4 = 0
-4 + -13r + 3r2 = 0 + 13r + -13r
-4 + -13r + 3r2 = 13r + -13r

Combine like terms: 13r + -13r = 0
-4 + -13r + 3r2 = 0

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

Divide each side by '3'.
-1.333333333 + -4.333333333r + r2 = 0

Move the constant term to the right:

Add '1.333333333' to each side of the equation.
-1.333333333 + -4.333333333r + 1.333333333 + r2 = 0 + 1.333333333

Reorder the terms:
-1.333333333 + 1.333333333 + -4.333333333r + r2 = 0 + 1.333333333

Combine like terms: -1.333333333 + 1.333333333 = 0.000000000
0.000000000 + -4.333333333r + r2 = 0 + 1.333333333
-4.333333333r + r2 = 0 + 1.333333333

Combine like terms: 0 + 1.333333333 = 1.333333333
-4.333333333r + r2 = 1.333333333

The r term is -4.333333333r.  Take half its coefficient (-2.166666667).
Square it (4.694444446) and add it to both sides.

Add '4.694444446' to each side of the equation.
-4.333333333r + 4.694444446 + r2 = 1.333333333 + 4.694444446

Reorder the terms:
4.694444446 + -4.333333333r + r2 = 1.333333333 + 4.694444446

Combine like terms: 1.333333333 + 4.694444446 = 6.027777779
4.694444446 + -4.333333333r + r2 = 6.027777779

Factor a perfect square on the left side:
(r + -2.166666667)(r + -2.166666667) = 6.027777779

Calculate the square root of the right side: 2.455153311

Break this problem into two subproblems by setting 
(r + -2.166666667) equal to 2.455153311 and -2.455153311.

Subproblem 1

r + -2.166666667 = 2.455153311 Simplifying r + -2.166666667 = 2.455153311 Reorder the terms: -2.166666667 + r = 2.455153311 Solving -2.166666667 + r = 2.455153311 Solving for variable 'r'. Move all terms containing r to the left, all other terms to the right. Add '2.166666667' to each side of the equation. -2.166666667 + 2.166666667 + r = 2.455153311 + 2.166666667 Combine like terms: -2.166666667 + 2.166666667 = 0.000000000 0.000000000 + r = 2.455153311 + 2.166666667 r = 2.455153311 + 2.166666667 Combine like terms: 2.455153311 + 2.166666667 = 4.621819978 r = 4.621819978 Simplifying r = 4.621819978

Subproblem 2

r + -2.166666667 = -2.455153311 Simplifying r + -2.166666667 = -2.455153311 Reorder the terms: -2.166666667 + r = -2.455153311 Solving -2.166666667 + r = -2.455153311 Solving for variable 'r'. Move all terms containing r to the left, all other terms to the right. Add '2.166666667' to each side of the equation. -2.166666667 + 2.166666667 + r = -2.455153311 + 2.166666667 Combine like terms: -2.166666667 + 2.166666667 = 0.000000000 0.000000000 + r = -2.455153311 + 2.166666667 r = -2.455153311 + 2.166666667 Combine like terms: -2.455153311 + 2.166666667 = -0.288486644 r = -0.288486644 Simplifying r = -0.288486644

Solution

The solution to the problem is based on the solutions from the subproblems. r = {4.621819978, -0.288486644}

See similar equations:

| -8+9x=19 | | 6r-4(r+8)=-14-r | | 8x+2=7x+11 | | -(3x-4y)+x=0 | | -8(x+7)=8x+24 | | 45x+39=45x+6 | | v/-3=-61 | | -35+6r=-5r-6(1+3r) | | 4x+x+1=10x-5x+1 | | 3y-yz=2zfory | | 3r-36=-3(5-8r) | | -4(p-4)=-2p+14 | | 3(4x+3)=16x+4-4x+5 | | 4(8n+2)=-25-n | | 8x+16x-10=6(4x+8) | | 3340+835+167+0+x=1.2x | | -21-5v=7(-7v-3) | | 7-6/7=1/7 | | 103=x+7 | | a-x/ax/x-a | | 40+7.5h=115 | | -6n+6(4n-1)=138 | | x/4/3=6 | | 2.3(-9x+9)=-6(15-x) | | 4x+4x-4=2(4x+2) | | 92=4(b+1)+7b | | 835+167+0+x=1.3x | | -5(-1-7x)=145 | | z/3.6=5 | | 167+0+x=1.2x | | 2(b+3c)= | | -7(-7+4m)=273 |

Equations solver categories