Respected sir...maybe the answer to 3.iii doesn't match with textbook

This question was asked in Ex 3.2, 3

Respected sir...maybe the answer to 3.iii doesn't match with textbook ans because b2=-10 and b1/b2= 5/3/-10
= -1/6 ....and not 1/6...
Then a1/a2 not equals to b1/b2
So its consistent.