Question

(5 + root 5)(5 - root 5)

Answer 1

answer is 20

use the identity (a+b)(a-b) = a^2 - b^2

hope that helps

please mark as brainliest

Answer 2

$(5 + \sqrt{5})(5 - \sqrt{5})$

$Using\:the\:identity\:of\:a^{2} - b^{2} = (a + b)(a - b),we\:get$

$(5^{2} - \sqrt{5}^{2})$

$(25 - 5)$

$(20)$