Cократите дробь 1) 5a+10/2a^2+13a+18 2) y^2-5y-36/81-y^2

1) 5a+10/ (2a^2+13a+18) 2a^2+13a+18=2 (a+2) (a+4,5) D=169-4*2*18=25a1=-2, a2=-4,55a+10/ (2a^2+13a+18)=5 (a+2) / (2 (a+2) (a+4,5)=5/ (2a+9) 2) (y^2-5y-36) / (81-y^2) y^2-5y-36=(y-9) (y+4) D=25-4*1*(-36)=169y1=9, y2=-4 (y^2-5y-36) / (81-y^2)=(y-9) (y+4) / (9-y) (9+y)=- (9-y) (y+4) / (9-y) (9+y)=- (y+4) / (9+y)