Question

(78)(82)=?
The formula of a+b=(a+b)(a-b)​

Answer 1

Answer:

$(78)(82)$

$\large\sf\purple{(80-2)(80+2)}$

$\small\sf\red{By \: using \: (a+b)(a-b) = a²-b²}$

(80)²-(2)²

6400-4

→6396

Answer 2

Answer:

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

=78+82=(78+82)(78-82)

=160=160×4

=4