Question

Хелп....... алгебра срочно (ТОЛЬКО ТРЕТИЙ) я третий пример решить не могу​

Answer 1

Ответ:

Объяснение:

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Answer 2

$80,3+\dfrac{3}{8} y^{2} -79,4-y^{2}-\dfrac{5}{6} y^{3}+y^{3}=(80,3-79,4)+\Big(\dfrac{3}{8}y^{2}-y^{2} \Big)+\Big(y^{3}-\dfrac{5}{6} y^{3}\Big)=\\\\\\=0,9+\dfrac{3-8}{8} y^{2}+\dfrac{6-5}{6} y^{3} =\boxed{0,9-\dfrac{5}{8}y^{2}+\dfrac{1}{6} y^{3}} \\\\\\y=-1\\\\\\0,9-\dfrac{5}{8}\cdot(-1)^{2}+\dfrac{1}{6}\cdot(-1)^{3}=0,9-\dfrac{5}{8}-\dfrac{1}{6}=0,9-\dfrac{5\cdot3+1\cdot4}{24} =\\\\\\=0,9-\dfrac{19}{24} =\dfrac{9}{10}-\dfrac{19}{24} =\dfrac{9\cdot12-19\cdot5}{120}=$

$=\dfrac{108-95}{120}=\boxed{\dfrac{13}{120}}$