I'm not sure but I think its c
Answer: 
Step-by-step explanation:
We need to apply the following identity:

Then, applying this, you know that for
:

We need to remember that:
and 
Therefore, we need to substitute these values into
.
Then, you get:



Answer:
i would be glad to help but i don't understand what to do
Step-by-step explanation:
Answer:
D.) 4x + y
Step-by-step explanation:
3x + x + y
Add 3
x and x
.
4
x + y
Answer: 84
Step-by-step explanation: 7 Times 12 because each foot is 12 inches