Question

I don’t know the answer

Answer 1

I believe the answer is -1.

Explanation:

So I distributed,

2 x 2 = 4

`-√(5)` x 2 =
`-2√(5)`

`√(5)` x 2 =
`2√(5)`

`√(5)` x
`-√(5)` = -5

4
`-2√(5)` +
`2√(5)` - 5 = ?

the radicals cancel out and 4 -5 = -1

Answer 2

(a+b) (a-b) =a^2 - b^2

In this question a=2, b=square root of 5

So 2*2=4 square root of 5 times square root of 5 is 5

4-5=-1