а)22p^4q²/99p^5q=2q/9p
б)7а/(а²+5а)=7а/а(а+5)=7/(а+5)
в)(y²-z²)/(2y+2z)=(y-z)(y+z)/2(y+z)=(y-z)/2
г)(a²-1)/(a²-2a+1)=(a-1)(a+1)/(a-1)²=(a+1)/(a-1)
a)(y-20)/4y -(5y-2)/y²=(y²-20y-20y+8)/4y²=(y²-40y+8)/4y²
б)1/(5c-d) - 1/(5c+d)=(5c+d-5c+d)/(25c²-d²)=2d/(25c²-d²)
в)7/(a+5) + (7a-3)/(a²+5a)=(7a+7a-3)/a(a+5)=(14a-3)/a(a+5)