for the columns where is less than or equal zero, use the first line of the function to calculate the value of f(x)

for every x greater than zero, use the second line to determine the value

hope this helps and gives some insight what to do.
if there are open questions left, feel free to ask them in the comments
have a beautiful day
-Alex
Answer:
I think 13 is C
Step-by-step explanation:
71+52= 123
180-123= 57
S=d/t
45=29/t
t=45/29
convert to min
t=45/29 *60=38.66min
Let C = the Chinese books.
Let E = the English language books.
C = 4/5 E
E - 300 = C - 180 Notice how you get this equation. You take 300 away from the English books and 180 from the Chinese and according to the question, you get an equal number of both. Put c = 4/5E into the second equation.
E - 300 = 4/5 E - 180 Add 300 to both sides.
E = 4/5 E - 180 + 300
E = 4/5 E + 120 Now subtract 4/5 E from both sidies.
E - 4/5 E = 120
1/5 E = 120 Now multiply by 5
E = 120 * 5
E = 600
So the number of books are
600 written in English
4/5 of 600 = 2400 /5 = 480 Chinese books.
English 600
Chinese 480
Answer:
Step-by-step explanation: 0.16