(7r+5)(7r-5)=0

Solution for (7r+5)(7r-5)=0 equation:

Simplifying
(7r + 5)(7r + -5) = 0

Reorder the terms:
(5 + 7r)(7r + -5) = 0

Reorder the terms:
(5 + 7r)(-5 + 7r) = 0

Multiply (5 + 7r) * (-5 + 7r)
(5(-5 + 7r) + 7r * (-5 + 7r)) = 0
((-5 * 5 + 7r * 5) + 7r * (-5 + 7r)) = 0
((-25 + 35r) + 7r * (-5 + 7r)) = 0
(-25 + 35r + (-5 * 7r + 7r * 7r)) = 0
(-25 + 35r + (-35r + 49r2)) = 0

Combine like terms: 35r + -35r = 0
(-25 + 0 + 49r2) = 0
(-25 + 49r2) = 0

Solving
-25 + 49r2 = 0

Solving for variable 'r'.

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

Add '25' to each side of the equation.
-25 + 25 + 49r2 = 0 + 25

Combine like terms: -25 + 25 = 0
0 + 49r2 = 0 + 25
49r2 = 0 + 25

Combine like terms: 0 + 25 = 25
49r2 = 25

Divide each side by '49'.
r2 = 0.5102040816

Simplifying
r2 = 0.5102040816

Take the square root of each side:
r = {-0.714285714, 0.714285714}