Question

without actual multiplication find 51²-49²​

Answer 1

51²-49²

by using a²-b²=(a+b) (a-b)

here a=51

b=49

51²-49²= (51+49) (51-49)

=(100) (2)

=200

by actual calculation,

=51*51-49*49

=2601−2401

=200