Объяснение:

2.

а) (14x-9+3x-25)/17x=(17x-34)/17x=17(x-2)/17x=(x-2)/x

б) (3*4a-5*5a)/(5a*4a)=(12a-25a)/20a^2=-13a/(20a^2)=-13/20a

в) (a(x+y)/xy^3)*(x^3y/8(x+y))=ax^2/8y^2

г) 16c^10/49в^6

3. (y-2)^2/(y^2-4)*y(y+2)/(10(y-2))=(y-2)/(y+2)*y(y+2)/(10(y-2))=y/10

80/10=8