21r^2-41r+18=

Solution for 21r^2-41r+18= equation:

Simplifying
21r2 + -41r + 18 = 0

Reorder the terms:
18 + -41r + 21r2 = 0

Solving
18 + -41r + 21r2 = 0

Solving for variable 'r'.

Factor a trinomial.
(2 + -3r)(9 + -7r) = 0

Subproblem 1
Set the factor '(2 + -3r)' equal to zero and attempt to solve:

Simplifying
2 + -3r = 0

Solving
2 + -3r = 0

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

Add '-2' to each side of the equation.
2 + -2 + -3r = 0 + -2

Combine like terms: 2 + -2 = 0
0 + -3r = 0 + -2
-3r = 0 + -2

Combine like terms: 0 + -2 = -2
-3r = -2

Divide each side by '-3'.
r = 0.6666666667

Simplifying
r = 0.6666666667
Subproblem 2
Set the factor '(9 + -7r)' equal to zero and attempt to solve:

Simplifying
9 + -7r = 0

Solving
9 + -7r = 0

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

Add '-9' to each side of the equation.
9 + -9 + -7r = 0 + -9

Combine like terms: 9 + -9 = 0
0 + -7r = 0 + -9
-7r = 0 + -9

Combine like terms: 0 + -9 = -9
-7r = -9

Divide each side by '-7'.
r = 1.285714286

Simplifying
r = 1.285714286
Solution
r = {0.6666666667, 1.285714286}