5Х2 - 5 =5(х2 -1) =5(Х-1)(5+1)
2а2 -8 =2(a^2 -4) =2(a -2)(a+2)
3ah^2 - 27a = 3a(h^2 -9)= 3a (h -3)(h +3)
2xy^2 -50x =2x(y^2 -25)=2x(y-5)(y+5)
1. -
2.3х;5у;-;30ху
3.6х;+;у;у^2
4.2у;-;7х;4у^2
5.10;х^2;-;+;100
6.8х;64х^2;-;+;9
8.
a6=-7.8 a19=-10.4 d-?
a6=a1+5d
a19=a1+18d
-7.8=a1+5d
-10.4=a1+18d
2.6=-13d
d=-0.2
14.
a1=-7 d=6 a91-?
a91=a1+90d
a91=-7+90*6
a91=-7+540
a91=533