1) (6р - 10а) (6р + 10а) = 36р^2 - 100а^2.
2) n^2 - 1 = ( n-1) ( n+1).
3) ( 11a - 7n)^2 = 121a^2 - 154an + 49n^2.
4) 169c^8 - 182c^4 + 49 = ( 13c^4 - 7)^2.
5) 225 - 16m^8 = 15^2 - 4(m^4)^2.
6) 16n^4 + 88n^2 +121 = (4n^2 + 11) ^2.
7) 49-(b+1) ^2= (7 -(b+1)) ( 7 + ( b +1)) = ( 7-b-1)( 7 +b+1).
76:9=8(ост.4)
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1)2x+7>=1 4x+9>-15 7x+9<2x-1
x-3<=1 2-x<=5 4+11x>9x-14
2x>=1-7 x>-6 x<-2
x<=1+3 x>=-3 x>5
x>=-3
x<=4