Ответы и объяснения

2013-09-23T22:11:26+04:00
1) (22 p^4 q^2)/(99p^5 q)=2q/9p  
2) 7a/(a^2+5a)=7a/(a(a+5))=7/(a+5)
3) (y^2-z^2)/(2y+2z)=((y-z)(y+z))/(2(y+z))=(y-z)/2
4) (a^2-1)/(a^2-2a+1)=((a-1)(a+1))/〖(a-1)〗^2 =(a+1)/(a-1)