To simplify the expressions, let's start with the first one:

5, (√20 – √45 + √5) √5

First, let's simplify the square roots:

√20 = √(4 * 5) = 2√5

√45 = √(9 * 5) = 3√5

Now, substitute these values back into the expression:

5, (2√5 – 3√5 + √5) √5

Combine like terms:

5, (2√5 – 3√5 + √5) √5 = 5, (0√5) √5

Any number multiplied by 0 is 0, so we have:

5, (0) √5 = 0

Therefore, the simplified expression is 0.

Now, let's simplify the second expression:

6, (2 + √5)^2 – (2 + √5)^2

First, let's expand the squares:

(2 + √5)^2 = (2 + √5)(2 + √5) = 4 + 2√5 + 2√5 + 5 = 9 + 4√5

Now, substitute this value back into the expression:

6, (9 + 4√5) – (9 + 4√5)

Combine like terms:

6, (9 + 4√5) – (9 + 4√5) = 6, 0

Any number subtracted from itself is 0, so we have:

6, 0 = 0

Therefore, the simplified expression is 0.