Question

Срочто пожалуйста♡♡♡♡​

Answer 1

Ответ:

$1)\ \ \displaystyle \frac{40-y}{30}=\frac{5}{6}\ \ \to \ \ 40-y=\frac{30\cdot 5}{6}\ \ ,\ \ 40-y=25\ \ ,\ \ y=15\\\\\\2)\ \ \displaystyle \frac{4}{7}=\frac{21-y}{28}\ \ \to \ \ 21-y=\frac{4\cdot 28}{7}\ \ ,\ \ 21-y=16\ \ ,\ \ y=5\\\\\\3)\ \ \displaystyle \frac{220}{y-49}=\frac{11}{13}\ \ \to \ \ y-49=\frac{220\cdot 13}{11}\ \ ,\ \ y-49=260\ \ ,\ \ y=309$

$4)\ \ \displaystyle \frac{21}{53}=\frac{220}{y+300}\ \ \to \ \ y+300=\frac{220\cdot 53}{21}\ \ ,\ \ y+300=\frac{11660}{21}\ \ ,\ \ y=\frac{5360}{21}\\\\\\5)\ \ \frac{29}{30}=\frac{78}{3y-2}\ \ \to \ \ 3y-2=\frac{30\cdot 78}{29}\ \ ,\ \ 3y-2=\frac{2340}{29}\ \ ,\ \ 3y=\frac{2398}{29}\\\\y=\frac{2398}{87}$

$6)\ \ \displaystyle \frac{52}{4y+2}=\frac{14}{3^3}\ \ \to \ \ 4y+2=\frac{52\cdot 3^3}{14}\ \ ,\ \ 4y+2=\frac{1404}{14}\ \ ,\ \ 4y=\frac{1376}{14}\\\\y=\frac{172}{7}\\\\\\7)\ \ \frac{13}{17}=\frac{7+2y}{85}\ \ \to \ \ 7+2y=\frac{13\cdot 85}{17}\ \ ,\ \ 7+2y=65\ \ ,\ \ 2y=58\ ,\ y=29$

$8)\ \ \displaystyle \frac{55}{90}=\frac{6-5y}{18}\ \ \to \ \ 6-5y=\frac{55\cdot 18}{90}\ \ ,\ \ 6-5y=11\ \ ,\ \ 5y=-5\ ,\ y=-1$