Answer:
12.8 seconds
Step-by-step explanation:
13.8-1=12.8.... unless I'm wrong?
Answer:
-9
Step-by-step explanation:

Your calculator can help with this.
Answer: i would show the picture with it too because I don’t think i could answer that without knowing what the angle looks like
Step-by-step explanation:
Let x the age of John
Amy's age = x + 9
from question, we get,
John's age + Amy's age = 23
x+(x+9)= 23
=> x + x + 9 = 23
=> 2x = 23 - 9
=> x = 14/2
=> x = 7