Good question!
First of all, you need to be aware of the following trigonometrical ratios\functions:
For angle A:
adjacent=12
opposite=35
hypotenuse=37
Hence:

I hope that
helps!
I am with you if you faced any difficulties!
Answer:
S
R
T
P
Q
Step-by-step explanation:
When you are told to estimate, you should be able to do the problem in your head.
8 7/12 is close to 8 1/2
4 7/8 is very nearly 5
4/10 is very nearly 1/2
8 1/2 - 5 - 1/2 First of all you can take the 1/2 away from 8 1/2
8 1/2 - 1/2 = 8
Now take away the 5
8 - 5 = 3
So the answer is very nearly
3 <<<<< answer.
Just for fun, I'll get the exact answer. Don't hand this one in. It is 3 37/120
You learn to estimate because you are trying to guess whether or not you've entered everything correctly into your calculator. When writing a test, this is a very handy skill to have developed.
Pythagoras says that x²+12²=13², so x=√(169-144)=√25=5