Respuesta :
49b^2 - 81 is (7b - 9)(7b + 9).
This is because 49 and 81 are the squares of 7 and 9 respectively, so these must be multiplied together. b^2 is b x b. Finally, it must be -9 and +9 to make -81, because when the signs are the same the result is a positive number.
(a^{2} -b^{2} )=(a+b)*(a-b)
in this problem we have
49b^{2} - 81 =7^{2} b^{2} -9^{2} =(7b+9)*(7b-9)
so the answer would be (7b-9)(7b+9)
hope this helps you have a great day
The factor of the expression 49b² − 81 will be (7b – 9) and (7b + 9).
What is a factorization?
It is a method for dividing a polynomial into pieces that will be multiplied together. At this moment, the polynomial's value will be zero.
The expression is given below.
⇒ 49b² − 81
Then the factor of the expression will be
⇒ (7b)² − 9²
⇒ (7b – 9)(7b + 9)
More about the factorization link is given below.
https://brainly.com/question/6810544
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