SOS!! HELP!! Помогите пожалуйста

[latex]= \frac{ a^{2} -9 b^{2} }{3ab} : \frac{a-3b}{3ab} = \frac{(a+3b)(a-3b)}{3ab} * \frac{3ab}{a-3b} =a+3b[/latex] [latex]8 \frac{4}{7} +3*4 \frac{1}{7} =8 \frac{4}{7}+12 \frac{3}{7} =21[/latex]

[latex] \frac{a^{2}-9b^{2}}{3ab}:( \frac{1}{3b}- \frac{1}{a}) = \frac{a^{2}-9b^{2}}{3ab}: \frac{a-3b}{3ab} = \frac{a^{2}-9b^{2}}{3ab} * \frac{3ab}{a-3b} = \frac{(a-3b)(a+3b)}{3ab}* \frac{3ab}{a-3b} \\ =a+3b= \frac{60}{7}+3* \frac{29}{7}= \frac{60}{7}+ \frac{87}{7}= \frac{147}{7}= 21 [/latex]