45=r^2(5)

Solution for 45=r^2(5) equation:

Simplifying
45 = r2(5)

Reorder the terms for easier multiplication:
45 = 5r2

Solving
45 = 5r2

Solving for variable 'r'.

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

Add '-5r2' to each side of the equation.
45 + -5r2 = 5r2 + -5r2

Combine like terms: 5r2 + -5r2 = 0
45 + -5r2 = 0

Add '-45' to each side of the equation.
45 + -45 + -5r2 = 0 + -45

Combine like terms: 45 + -45 = 0
0 + -5r2 = 0 + -45
-5r2 = 0 + -45

Combine like terms: 0 + -45 = -45
-5r2 = -45

Divide each side by '-5'.
r2 = 9

Simplifying
r2 = 9

Take the square root of each side:
r = {-3, 3}