1) =5(x-3)-3(x-3)^2=(x-3)(5-3x+9)=(x-3)(14-3x)
2) =0,73(0,73+0,27)+0,27=0,73+0,27=1
3)12^5-18^4=2^5*6^5-3^4*6^4=6^4(32*6-81)=6^4(192-81)=6^4*111,
б) =6^4*111=6^3*666, (666:37)
4)2x^2-x=0, x(2x-1)=0, x=0, x=1/2
5(x-3)-(6-2x)^2=0, 5(x-3)-(2(3-x)^2=0, (x-3)(5-4(x-3))=0, (x-3)(8-4x)=0, x=3, x=2
1÷4=5х÷8
5х×4=8×1
20х=8
х=8/20
х=2/5
х= 0,4
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