15*(22-х)=13*(22+х) 36*(х+2)=48*х х/25=х+420/60 (5/125/100)х+5х=21

15*(22-х)=13*(22+х)
330-15х=286+13х
330-286=13х+15х
44=28х
х= $\frac{44}{28}$
х= $\frac{11}{7}$
х= $1\frac{4}{7}$

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36*(х+2)=48*х
36x+72=48x
72=48x-36x
72=12x
x=6

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х/25=х+420/60
x:25=x+7
x=25(x+7)
x=25x+175
x-25x=175
-24x=175
x= $- \frac{175}{24}$
x=- $7 \frac{7}{24}$