1) 3х=8-2у, 3х=8-2*(-3,5), 3х=8+15, 3х=23, х=23/3, х=7 целых 2/3
2) 2(8-2у)+6у=9, 16-4у+6у-9=0, 7+2у=0, 2у=-7, у=-7/2, у=-3.5
Ответ: х=7 целых 2/3 ;у=-3.5
A) (2m+3)-(m-1))*(2m+3+(m-1))
(2m+3-m-+1)*(2m+3+m-1)
(m+4)*(3m+2)
Б) 4k^2+2kn+8k^3
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