Question

show that (5+root5)(5-root5) is rational number

Answer 1

(5+√5)(5-√5)
=(5)^2-(√5)^2
=25-5
=20 which is a rational number

Answer 2

(5+√5) (5-√5)
(5)^2 - (√5)^2
25-5
20

here the answer is 20 ,so it is a rational number because it is in the form of p/q
20/1