<PRE><B>Question 1035736</B>
(5x^2 - 7) * (5x^2 + 7) is equal to:


5x^2 * (5x^2 + 7) - 7 * (5x^2 + 7).


the first part this is 5x^2 * (5x^2 + 7).


5x^2 * (5x^2 + 7) is equal to 5x^2 * 5x^2 + 5x^2 * 7.
simplify this to get 25x^4 + 35x^2.


the second part of this is - 7 * (5x^2 + 7).


- 7 * (5x^2 + 7) is equal to -7 * 5x^2 - 7 * 7.
simplify this to get -35x^2 - 49.


put these 2 pieces together to get 25x^4 + 35x^2 - 35x^2 - 49.
combine like terms to get 25x^4 - 49.


the simplified expression is 25x^4 - 49.










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