Question

СРОЧНО 30 БАЛОВ ААААА​

Answer 1

$\frac{xa-9a+3x-27}{x^{2}-81 } =\frac{a(x-9)+3(x-9)}{(x-9)(x+9)}=\frac{(x-9)(a+3)}{(x-9)(x+9)} = \frac{a+3}{x+9} =\frac{-42+3}{-14+9} =\frac{-39}{-5} = 7.8$