20r^2=4r

Solution for 20r^2=4r equation:

Simplifying
20r2 = 4r

Solving
20r2 = 4r

Solving for variable 'r'.

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

Combine like terms: 4r + -4r = 0
-4r + 20r2 = 0

Factor out the Greatest Common Factor (GCF), '4r'.
4r(-1 + 5r) = 0

Ignore the factor 4.
Subproblem 1
Set the factor 'r' equal to zero and attempt to solve:

Simplifying
r = 0

Solving
r = 0

Move all terms containing r to the left, all other terms to the right.

Simplifying
r = 0
Subproblem 2
Set the factor '(-1 + 5r)' equal to zero and attempt to solve:

Simplifying
-1 + 5r = 0

Solving
-1 + 5r = 0

Move all terms containing r to the left, all other terms to the right.

Add '1' to each side of the equation.
-1 + 1 + 5r = 0 + 1

Combine like terms: -1 + 1 = 0
0 + 5r = 0 + 1
5r = 0 + 1

Combine like terms: 0 + 1 = 1
5r = 1

Divide each side by '5'.
r = 0.2

Simplifying
r = 0.2
Solution
r = {0, 0.2}