Question

(5+√5)(5-√5) please do my friends once do friends​

Answer 1

Answer:

20

Step-by-step explanation:

(a+b)(a-b),= a

×a -b×b

Answer 2

Answer:

20

Step-by-step explanation:

because

here,

we are applying a identity

identity: (a+b) (a-b) = a² – b²

so according to the identity,

$5 + \sqrt{5} 5 - \sqrt{5 } = {5}^{2} - \sqrt{5}^{2} \\ = 25 - \sqrt{5 \times 5} \\ = 25 - 5 \\ 20$

so,

the answer is 20