(5r-1)(r+3)=

Solution for (5r-1)(r+3)= equation:

Simplifying
(5r + -1)(r + 3) = 0

Reorder the terms:
(-1 + 5r)(r + 3) = 0

Reorder the terms:
(-1 + 5r)(3 + r) = 0

Multiply (-1 + 5r) * (3 + r)
(-1(3 + r) + 5r * (3 + r)) = 0
((3 * -1 + r * -1) + 5r * (3 + r)) = 0
((-3 + -1r) + 5r * (3 + r)) = 0
(-3 + -1r + (3 * 5r + r * 5r)) = 0
(-3 + -1r + (15r + 5r2)) = 0

Combine like terms: -1r + 15r = 14r
(-3 + 14r + 5r2) = 0

Solving
-3 + 14r + 5r2 = 0

Solving for variable 'r'.

Factor a trinomial.
(-3 + -1r)(1 + -5r) = 0

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

Simplifying
-3 + -1r = 0

Solving
-3 + -1r = 0

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

Add '3' to each side of the equation.
-3 + 3 + -1r = 0 + 3

Combine like terms: -3 + 3 = 0
0 + -1r = 0 + 3
-1r = 0 + 3

Combine like terms: 0 + 3 = 3
-1r = 3

Divide each side by '-1'.
r = -3

Simplifying
r = -3
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 = {-3, 0.2}