5x+48:4=20:10+2×10
5х+12=2+20
5х=2+20-12
5х=10
х=10:5
х=2
Ответ:2
замена х2=t t>0
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5x=0
1+x=0
2-IxI=0
x1=0
x2= -1
x3= 2
x4= -2