The temperature started at 15 degrees.
It dropped 25 degrees.
Subtract 25 from 15:
15 - 25 = -10
The temperature was -10 degrees.
The activity pictured is called goat tying.

Solution:
Given data:
and 
To find F(x) + G(x):
Adding two functions which gives another function.
Substitute F(x) and G(x), we get





Hence, 