What is the factorization of 49b2 − 81?

Mathematics

2 answers:

Soloha48 [4]2 years ago

6 0

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

Ann [662]2 years ago

5 0

Answer:

Step-by-step explanation:

49b² - 81 = (7b)² - 9 ²

by identity : 49b² - 81 = (7b - 9)( 7b + 9)

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pantera1 [17]

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