1) "Subtract -7a+1 from 7+a" means -7a+1 is getting taken away from 7+a, so this can be mathematically expressed as:
Starting expression: (7+a)-(-7a+1)
Distributive property with negatives: 7+a+7a-1
Combine like terms: 6+8a
So the answer for the first one is 6+8a
2) "Subtract -4v-2 from -2-5v" means -4v-2 is getting taken away from -2-5v, so this can be mathematically expressed as:
Starting expression: (-2-5v)-(-4v-2)
Distributive property with negatives: -2-5v+4v+2
Combine like terms: -v
So the answer for the second one is -v
Hope these explanations are clear.