7. e and f
9. c.
sorry didn't understand 8
Answer:
A. $459
Step-by-step explanation:
What do you mean by this question?
Write it out as a set of equation:
Let x be number of 8 cent stamps, y be 10 cent stamps, and z be 2 cent stamps.
x=y
z=x+y
8x+10y+2z=440
Lets first solve for x:
from x=y and z=2x(from first equation) the last equation is
8x+10x+4x=440
22x=440
x=20
know that x=20, you also know that y=20 as well, since z=x+y, z=40.
So 20 8-cent stamps, 20 10-cent stamps, and 40 2-cent stamps.
Answer:
Step-by-step explanation:
The given function is .
The domain refers to all values of x for which this function is defined.
Recall that: the domain of 
is 
And we know is the reciprocal of .
Therefore the complement of the domain of which is ![(-\infty,-1]\cup [1,+\infty)](https://tex.z-dn.net/?f=%28-%5Cinfty%2C-1%5D%5Ccup%20%5B1%2C%2B%5Cinfty%29)
is the domain of
