If (64)2 – (36)2 = 20 x x, then x = ?

Question:
If (64)2 – (36)2 = 20 x x, then x = ?

[A].

70

[B].

120

[C].

180

[D].

140

Answer: Option D

Explanation:

20 x x = (64 + 36)(64 – 36) = 100 x 28

x =	100 x 28	= 140
	20