Remark
I would have had the answer a whole lot sooner if I would have read the question properly. The figure in the circle is called a cyclic quadrilateral. It has the odd property that the angles that are opposite each other add up to 180o.
So DEB + DCB = 180o
DEB = 180 - 87
DEB = 93o
Note: The arcs marked 60 and 76 have nothing whatever to do with this problem.
We need to know the definition of the "combined function" h(x). I'm going to guess--by looking at answers--that the function is

making it

This function is undefined wherever the denominator is equal to 0 (division by zero is undefined). Factor the denominator.

The two values of x that make the denominator 0 are 3 and -3, otherwise written

.
Answer:
580
Step-by-step explanation:
4*100=400
4*40=160
4*5=20
add them all up, you get 580
Answer: 9
Step-by-step explanation:
Domain are x values (independent variable);
Speed would be independent so what speeds can be used ? -30 mph, 30 mph, 1000 mph?
Can a car go 0 mph?
What is realistic?
I would say 0 greater or equal to x greater than whatever you think is beyond the max that a car can go.