Question

evaluate without multiplying directly:
103×97​

Answer 1

Step-by-step explanation:

(100 + 4) (100 - 4)

by using identity

(x + a) (x + b) = x² + (a+b)*x + ab

So,

x = 100 , a = 4 , b = (-4)

= (100)² + { 4 + (-4) }*100 + 4*(-4)

= 10000 + (4 - 4)*100 - 16

= 10000 + 0*100 - 16

= 10000 - 16

= 9984

.

Answer 2

Answer:

(100+3)(100-3)

100²-3²

10000-9

9991