8.50x+100=308.25
subtract 100 from both sides
8.5x = 208.25
divide 8.5 from both sides
x= 24.5 hours worked
0.333.... as a fraction is 1/3.
Answer:

Step-by-step explanation:
The function that we have to study in this problem is

The domain of a function is defined as the set of all the possible values of x that the function can take.
For a square-root function, there are some limitations to the possible value of the argument in the root.
In particular, the argument of a square root must be equal or greater than zero, because the square root of a negative number is not defined.
Therefore, in this case, we have to set the following condition for the domain:

And by solving, we get

which means that the domain of this function is all real numbers equal or greater than 5.
#13 would be 100%.
#15 would be $9.90.
#17 would be 408.
#19 would be 27840.
#21 would be 26.
Sorry for the late reply.
C since that's the only triangle where A^2+B^2=C^2 (36+64=100).