The expression x^2 + 9 is an algebraic expression
x^2 + 9 cannot be factored because it is not a difference of two squares
The expression is given as:
x^2 + 9
Express 9 as the square of 3
x^2 + 3^2
The above expression is not a difference of two squares
Hence, x^2 + 9 cannot be factored because it is not a difference of two squares
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