Question

evaluate 83×77 by using suitable identity​

Answer 1

Answer:

$(a + b)(a - b). \\ (80 + 3)(80 - 3) \\ 80 { }^{2} - 3 {}^{2} \\ 6400 - 9 \\ = 6391$

Answer 2

Answer:

(80+3)*(80-3)

(a+b) *(a-b)

(a^2-b^2)

(80^2-3^2)

(6400-9)

6391