Ответ:

Пошаговое объяснение:

7/(15y)=30;

7=450y;

y=7/450.

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1/(y+2)=6;

1=6(y+2);

1=6y+12;

6y= -11;

y= -11/6.

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1/(2y+1)=12;

1=12(2y+1);

1=24y+12;

24y=-11;

y=-11/24.

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(4+1)/(2+y)=20;

5=20(2+y);

5=40+20y;

20y=-35;

y=-35/20= -7/4=-1 3/4=-1.75.

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5/(3(y-1))=15;

5=15*3(y-1);

5=45y-45;

45y=50;

y=50/45=10/9=1 1/9.

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2(5+y)/6=30;

10+2y=180;

2y=170;

y=170/2=85.

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2(5+3)/4=5/y;

16y=20;

y=20/16=5/4=1 1/4 = 1.25.

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(1+y)/5=12;

1+y=60;

y=59.