4r^2-20r=.25

Simple and best practice solution for 4r^2-20r=.25 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 4r^2-20r=.25 equation:


Simplifying
4r2 + -20r = 0.25

Reorder the terms:
-20r + 4r2 = 0.25

Solving
-20r + 4r2 = 0.25

Solving for variable 'r'.

Reorder the terms:
-0.25 + -20r + 4r2 = 0.25 + -0.25

Combine like terms: 0.25 + -0.25 = 0.00
-0.25 + -20r + 4r2 = 0.00

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

Divide each side by '4'.
-0.0625 + -5r + r2 = 0.00

Move the constant term to the right:

Add '0.0625' to each side of the equation.
-0.0625 + -5r + 0.0625 + r2 = 0.00 + 0.0625

Reorder the terms:
-0.0625 + 0.0625 + -5r + r2 = 0.00 + 0.0625

Combine like terms: -0.0625 + 0.0625 = 0.0000
0.0000 + -5r + r2 = 0.00 + 0.0625
-5r + r2 = 0.00 + 0.0625

Combine like terms: 0.00 + 0.0625 = 0.0625
-5r + r2 = 0.0625

The r term is -5r.  Take half its coefficient (-2.5).
Square it (6.25) and add it to both sides.

Add '6.25' to each side of the equation.
-5r + 6.25 + r2 = 0.0625 + 6.25

Reorder the terms:
6.25 + -5r + r2 = 0.0625 + 6.25

Combine like terms: 0.0625 + 6.25 = 6.3125
6.25 + -5r + r2 = 6.3125

Factor a perfect square on the left side:
(r + -2.5)(r + -2.5) = 6.3125

Calculate the square root of the right side: 2.512468905

Break this problem into two subproblems by setting 
(r + -2.5) equal to 2.512468905 and -2.512468905.

Subproblem 1

r + -2.5 = 2.512468905 Simplifying r + -2.5 = 2.512468905 Reorder the terms: -2.5 + r = 2.512468905 Solving -2.5 + r = 2.512468905 Solving for variable 'r'. Move all terms containing r to the left, all other terms to the right. Add '2.5' to each side of the equation. -2.5 + 2.5 + r = 2.512468905 + 2.5 Combine like terms: -2.5 + 2.5 = 0.0 0.0 + r = 2.512468905 + 2.5 r = 2.512468905 + 2.5 Combine like terms: 2.512468905 + 2.5 = 5.012468905 r = 5.012468905 Simplifying r = 5.012468905

Subproblem 2

r + -2.5 = -2.512468905 Simplifying r + -2.5 = -2.512468905 Reorder the terms: -2.5 + r = -2.512468905 Solving -2.5 + r = -2.512468905 Solving for variable 'r'. Move all terms containing r to the left, all other terms to the right. Add '2.5' to each side of the equation. -2.5 + 2.5 + r = -2.512468905 + 2.5 Combine like terms: -2.5 + 2.5 = 0.0 0.0 + r = -2.512468905 + 2.5 r = -2.512468905 + 2.5 Combine like terms: -2.512468905 + 2.5 = -0.012468905 r = -0.012468905 Simplifying r = -0.012468905

Solution

The solution to the problem is based on the solutions from the subproblems. r = {5.012468905, -0.012468905}

See similar equations:

| 4xy-28x+7y-49= | | -6(6-8a)-3(8-2a)=-6 | | 8(x-5)-(2+7x)=4 | | 2/3(3x-12)=1/2(4x-4) | | 1.3y=y+1+2 | | (x-1)(x-2)-12= | | -38-2=10x+21 | | r^2+81v^2= | | 35b=70 | | 2.5e+3=.5e+15 | | 2/3(3x-12)=1/2 | | 3x-5+7x=5x+2 | | 4x+3*(2x-16)=12 | | 4(x+12)=64 | | x-a+2=2ax-3x-11 | | 3dx=3x-4 | | 11g=69 | | 40+x=10 | | 3w-12=6w+6 | | -4.5t^2+43t+2=0 | | 588/7 | | 90=5x+2 | | -2=-3y-18-5y | | 125x+225y=6000 | | 262.50/7=x | | 90=2x+5 | | 7+1/8l=-2 | | 262.50=7/5x | | 2x(-5)= | | 8x+220=15x | | 1.5h(6)+40h=588 | | 4x+3*(0,5x+4)=12 |

Equations solver categories