simplify: 81 x 81 + 68 x 68 - 2 x 81 x 68. Choose the correct option
A) 169	B) 159	C) 189	D) 179	E) 219
<gadget id="calculator">81 + 81</gadget>
<output>162</output>

<result>A</result>
simplify: 81 x 81 + 68 x 68 - 2 x 81 x 68.
add(81, 81)
= ( 81 ) ^ 2 + ( 68 ) ^ 2 – 2 x 81 x 68 = a ^ 2 + b ^ 2 – 2 ab , where a = 81 , b = 68 = ( a - b ) ^ 2 = ( 81 – 68 ) ^ 2 = ( 13 ) ^ 2 = 169 . answer is a .