Attached the solution and work.
Cara's brother is 7 years old.
14 is twice as much as 7 (7 * 2 = 14).
Okay so basically when two people answer your questions it should give you the option to give brainliest otherwise sometimes it takes a few days to give it to someone. And for your question does it give any number options.?
Edit: f(-1)= 1 then f(1)= -10.