Answer:
Look below.
Step-by-step explanation:
Good ol' Pythagorean Theorem.
To find the short side of the larger triangle, we'll use this equation:

You can solve the rest on your own.
Use the same type of equation for the smaller triangle, except your b would be the hypotenuse, so that equation would look something like this:

Hope it helped! Also, there seems to be a help video, if you didn't understand this explanation, why don't you go ahead and watch it?
Answer:
The correct way to evaluate this expression is my following the order of operations PEMDAS
P=Paranthesis
E=Exponents
M/D=multiply/divide
A/S=add/subtract
The first step in 48-(29-17) is to do what's inside the paranthesis
48-12 (29-17=12)
Then you would subtract 48-12
48-12=36
Your final answer is
36
Hope this helps ;)