Question

(79)², evaluate , please solve by 100​

Answer 1

Answer:

(79)² can be written as :

(100-21)(100-21).

(100-21)²

Using the identity

(a-b)²= (a)²+(b)²-2(a)(b)

(100)²+(21)²-2(100)(21)

10000+441-4200

=6241

Answer 2

Answer:(79)^2=(70+9)^2

=70(70+9)+9(70+9)

=70^2+70×9+9×70+9^2

= 4900+630+630+81

=6241