107 x 107 + 93 x 93 = ?

by
Question: 107 x 107 + 93 x 93 = ?

[A].

19578

[B].

19418

[C].

20098

[D].

21908

Answer: Option C

Explanation:

107 x 107 + 93 x 93 = (107)2 + (93)2
= (100 + 7)2 + (100 – 7)2
= 2 x [(100)2 + 72]       [Ref: (a + b)2 + (a – b)2 = 2(a2 + b2)]
= 20098