Решите пропорциюа)21:y=14:4б)-2x+1  =   -2-3x     4      =      5в)4 целых 1/8:5,5=(x-2,1):0,4

[latex] \frac{21}{y} = \frac{14}{4} \\ \\ 14y=21*4 \\ 14y=84 \\ y=6[/latex] [latex] \frac{-2x+1}{4} = \frac{-2-3x}{5} \\ \\ 4(-2-3x)=5(-2x+1) \\ -8-12x=-10x+5 \\ -12x+10x=5+8 \\ -2x=13 \\ x=-6,5[/latex] [latex]4 \frac{1}{8} :5,5=(x-2,1):0,4 \\ \\ \frac{33}{8} : \frac{11}{2} =(x- \frac{21}{10} ): \frac{2}{5} \\ \\ \frac{33}{8} * \frac{2}{11} =(x- \frac{21}{10} )* \frac{5}{2} \\ \\ \frac{3}{4} =(x- \frac{21}{10} )* \frac{5}{2} \\ \\ \frac{3}{4}:\frac{5}{2} =x- \frac{21}{10} \\ \\ \frac{3}{4}*\frac{2}{5} =x- \frac{21}{10} \\ \\ \frac{3}{10}=x- \frac{21}{10} \\ \\ x=\frac{3}{10}+\frac{21}{10}=\frac{24}{10}=2,4[/latex]