r^2+9=(3+r)(3+r)

Solution for r^2+9=(3+r)(3+r) equation:

Simplifying
r2 + 9 = (3 + r)(3 + r)

Reorder the terms:
9 + r2 = (3 + r)(3 + r)

Multiply (3 + r) * (3 + r)
9 + r2 = (3(3 + r) + r(3 + r))
9 + r2 = ((3 * 3 + r * 3) + r(3 + r))
9 + r2 = ((9 + 3r) + r(3 + r))
9 + r2 = (9 + 3r + (3 * r + r * r))
9 + r2 = (9 + 3r + (3r + r2))

Combine like terms: 3r + 3r = 6r
9 + r2 = (9 + 6r + r2)

Add '-9' to each side of the equation.
9 + -9 + r2 = 9 + 6r + -9 + r2

Combine like terms: 9 + -9 = 0
0 + r2 = 9 + 6r + -9 + r2
r2 = 9 + 6r + -9 + r2

Reorder the terms:
r2 = 9 + -9 + 6r + r2

Combine like terms: 9 + -9 = 0
r2 = 0 + 6r + r2
r2 = 6r + r2

Add '-1r2' to each side of the equation.
r2 + -1r2 = 6r + r2 + -1r2

Combine like terms: r2 + -1r2 = 0
0 = 6r + r2 + -1r2

Combine like terms: r2 + -1r2 = 0
0 = 6r + 0
0 = 6r

Solving
0 = 6r

Solving for variable 'r'.

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

Add '-6r' to each side of the equation.
0 + -6r = 6r + -6r
Remove the zero:
-6r = 6r + -6r

Combine like terms: 6r + -6r = 0
-6r = 0

Divide each side by '-6'.
r = 0

Simplifying
r = 0