Simplify: 81 X 81 + 68 X 68-2 x 81 X 68.  Answers:
A) 169
B) 159
C) 189
D) 179
E) 219
= (81)^2 + (68)^2 – 2x 81 x 68 = a^2 + b^2 – 2ab,Where a =81,b=68   = (a-b)^2 = (81 –68)^2 = (13)^2 = 169.   169nswer is 169.
<result>A</result>
Simplify: 81 X 81 + 68 X 68-2 x 81 X 68.