Question

$sqrt{a}+ sqrt{4}= sqrt{81}$
чему равно а=?

Answer 1

!!!!!!!!!!!!!!!!!!!!!!

Answer 2

$sqrt{a}+ sqrt{4}= sqrt{81} \ \ sqrt{a} = sqrt{81} - sqrt{4} \ \ sqrt{a} = 9 - 2 = 7 \ \ (sqrt{a})^2 = 7^2 \ \ a = 49$

Ответ: a = 49