Please explain how to solve this:

Question

(�ã5 + 4)(�ã5 - 1)

Answer 1

there's nothing to solve
do you want to multiply

(√5 + 4)(√5 - 1) ?
Just multiply like any binomials:

√5√5 + 4√5 - 1√5 - 4*1
= 5 + 3√5 - 4
= 1 + 3√5

Answer 2

We are to multiply & simplify. My teacher foiled it but I think she made a mistake because the answer she gave was 1+4�ã5 & someone else said the answer should be 3�ã5+1. I'm confused on the foiling.

She foiled it this way:
�ã5*�ã5 -�ã5 + 5*�ã5 - 4 = 5 + 4*�ã5 - 4
= 1+4�ã5