Question

evaluate (12a-9)(12a+9)​

Answer 1

Answer:

$(12a + 9b)(12a - 9b)$

$(12a) {}^{2} - (9 b) {}^{2}$

$144a {}^{2} - 81 b {}^{2}$

Answer 2

a = 9/11 ☑️

Explanation :

(12a - 9) (12a + 9)

By multiplying both

⟹ 144a²+ 108a - 108a - 81 = 0

(we cancelled 108a with -108a)

⟹ 144a² - 81 = 0

⟹ 144a² = 81

⟹ a² = 81/144

⟹ a = √81 / √ 144

⟹ a = 9/11