Question

Помогите будьласка!!!!!!​

Answer 1

$\displaystyle\bf\\1)\\\\-15+(-17)=-32\\\\-15-(-17)=-15+17=2\\\\\boxed{-32\cdot 2=-64}\\\\2)\\\\3,9\cdot(-27,1)=-105,69\\\\\boxed{-105,69+(-5,81)=-111,5}\\\\3)\\\\\frac{2}{9} +\Big(-\frac{1}{3} \Big)=\frac{2}{9} -\frac{3}{9} =-\frac{1}{9} \\\\\\\boxed{\Big(-\frac{1}{9} \Big)^{2} =\frac{1}{81} }$