Решиеь ​

1) 4ab/(a+4b)*((a²-16b²)/4ab)= (a-4b)(a+4b)/(a+4b)= a-4b

a-4b=1/3-4*5/6= 1/3-10/3= -9/3= -3

2) ((a²-9b²)/3ab):((a-3b)/3ab)= (a-3b)(a+3b)/3ab*3ab/(a-3b)= a+3b

a+3b=22/7+3*9/7= 22/7+27/7= 49/7= 7