а) х¹ + х² = 4
х¹ • х² = 3
х¹ = 1
х² = 3
б) х¹ + х² = -6
х¹ • х² = 8
х¹ = -4
х² = -2
2/3(х-5)+1,1/3(х+1)=9
2/3(x-5+2x+2)=9
3x-3=27/2
x-1=9/2
x=11/2
х+1/2х+1/3х=33
x(1+1/2+1/3)=33
x*11/6=33
x=1/2
* - умножить.
S1=1/2*(5*6)=2/30=15
S2=1/2*(1*6)=2/6=3
S3=18S(всего) = 15+3+18=36
см.влож
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