tolong jawabkan no 2 beserta caranya sebelumnya terima kasih.

a) 2a + b - c
= 2. 9/4 + 3/2 -5/6
= 54/12 + 18/12 + 10/12
= 62/12
= 31/6
=5 1/6

b) a. 3b : c
= 9/4 x 9/2 : 5/6
= 81/8 × 6/5 (dibalik karena pembagian
= 464/40
= 58/5
= 11 3/5

c) b-c
= 3/2 - 5/6
= 18/12 - 10/12
= 8/12
= 2/3

semoga membantu:)

yang b.) ax 3b : c
= 9/4 x 9/2 : 5/6
= 81/8x6/5 = 486/40 = 12 6/40= 12 3/20