2 years ago

10. (07.07 LC)

Mathematics

1 answer:

Serhud [2]2 years ago

6 0

Answer:

Step-by-step explanation:

(9x - 4)(9x + 4) = ax² - b

81x² - 36x + 36x - 16

= 81x² - 16

=> a = 81

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