- 5х(2-х)=+10х+25-10х-5=-4+25
16y+2(y-4)=16y+2y-8=18y+8
81-=(9-a)(9+a)
5-5=5(-)
3-6хy+3хy=3х(х-6y+3y)
16y+2(y-4)=16y+2y-8=18y+8
81-
=(9-a)(9+a)
5
-5
=5(
-
)
3
-6хy+3хy=3х(х-6y+3y)