Use One of the Appropriate Patterns $( a + b ) ^ { 2 } = a ^ { 2 } + 2 a b + b ^ { 2 }$

Multiple Choice

Use one of the appropriate patterns $( a + b ) ^ { 2 } = a ^ { 2 } + 2 a b + b ^ { 2 }$ ; $( a - b ) ^ { 2 } = a ^ { 2 } - 2 a b + b ^ { 2 }$ ; $( a + b ) ( a - b ) = a ^ { 2 } - b ^ { 2 }$ to find the following product. $( 9 + 6 n ) ( 9 - 6 n )$

A) $81 - 36 n ^ { 2 }$
B) $81 - 6 n ^ { 2 }$
C) $9 - 36 n ^ { 2 }$
D) $81 + 36 n ^ { 2 }$
E) none of these