Answer:
Final factor is (x-9)(x+4)
Step-by-step explanation:
Given expression is
.
Now we need to factor that expression

Find two numbers whose product is -36 and sum is -5.
Two such numbers oare -9 and +4. So we get:



Hence final factor is (x-9)(x+4)
He burns off 750 calories every 3 hours. 250 multiplied my 3 is 750. 3 being the hours and 250 being the calories burned every hour
Given the function 
1. The domain of the function (possible values for x) is:

2. The range of the function (possible values for y) is:

3. x-intercept is when y=0, then

Therefore, x-intercept is at point 
4. There are no y-intercepts.
5. The graph of the function is decreasing (see attached diagram)