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

#SPJ2