Answer :
your question is a difference of squares. both terms that need to be factored are squared. to solve take the square root of each put into two terms one of addition and one of subtraction.
anwser= (5x-9)(5x+9)
the reason this works is because when you foil you get
25x²-45x+45x-81
the middle terms cancel revealing
25x²-81
anwser= (5x-9)(5x+9)
the reason this works is because when you foil you get
25x²-45x+45x-81
the middle terms cancel revealing
25x²-81
