F(-5) is 23-D
Line change is B
Lets get all the information we need first.
A week has 7 days, you practice 30 min each day, so in a week you will practice a total time t of 30 min for 7 times, that is:
t = 7day(30 min/day)
t = 210 min
So in a week you will practice a total of 210 minutes.
Answer:
4/25
Step-by-step explanation:

Substitute x = 3 in any given equations. I will do in y = - x + 1

Therefore the answer is (3,-2)