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

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

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

Multiply (3 + -5r) * (5 + r)
(3(5 + r) + -5r * (5 + r)) = 0
((5 * 3 + r * 3) + -5r * (5 + r)) = 0
((15 + 3r) + -5r * (5 + r)) = 0
(15 + 3r + (5 * -5r + r * -5r)) = 0
(15 + 3r + (-25r + -5r2)) = 0

Combine like terms: 3r + -25r = -22r
(15 + -22r + -5r2) = 0

Solving
15 + -22r + -5r2 = 0

Solving for variable 'r'.

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

Subproblem 1
Set the factor '(3 + -5r)' equal to zero and attempt to solve:

Simplifying
3 + -5r = 0

Solving
3 + -5r = 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 + -5r = 0 + -3

Combine like terms: 3 + -3 = 0
0 + -5r = 0 + -3
-5r = 0 + -3

Combine like terms: 0 + -3 = -3
-5r = -3

Divide each side by '-5'.
r = 0.6

Simplifying
r = 0.6
Subproblem 2
Set the factor '(5 + r)' equal to zero and attempt to solve:

Simplifying
5 + r = 0

Solving
5 + r = 0

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

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

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

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

Simplifying
r = -5
Solution
r = {0.6, -5}