6.4 ANSWER normal path
a) 5a . 2b
= 10ab
b) 7b . 9b
= 63b2
c) 18y . 0 . 3b
= 0
d) -s . u . -p
= -su . -p
= psu
e) 3a + 7a + 101b - a
= 10a + 101b - a
= 9a + 101b
f) 10pq + pq . 43 - 2
= 10pq + 43pq - 2
= 53pq - 2
g) 5gh . g . 4 . a
= 5g2h . 4 . a
= 20g2h . a
= 20ag2h
h) 6a + 7 . 2a - 5
= 6a + 14a - 5
= 20a - 5
i) 5ab + 6a + 7b + 3ab + 2a . -3b + 4a
= 5ab + 6a + 7b + 3ab - 6ab + 4a
= 2ab + 10a + 7b