Answer:
>>> Letter A. ( x^2 + 7 ) ( x^2 - 7 )
Step-by-step explanation:
[tex] {x}^{4} - 49 \\ \\ {x}^{2 \times 2} - 49 \\ \\ {x}^{2 \times 2} - {7}^{2} \\ \\ use \: \: {a}^{mm} = ( {a}^{n} {)}^{m} \\ \\ ( {x}^{2} {)}^{2} - {7}^{2} \\ \\ use \: \: {a}^{2} - {b}^{2} = (a - b)(a + b) \\ \\ ( {x}^{2} + 7)( {x}^{2} - 7)[/tex]
hope its help
