Step-by-step explanation:
1. 2/5 + 7/10 - 9/12
= 2/5 + 7/10 - 3/4
= 8/20 + 14/20 - 15/20
= (8 + 14 - 15)/20
= 7/20
2. Lim x→2 (2x + 7)
= (2(2) + 7))
= (4 + 7)
= 11
