Answer:
the answer is D: undefined becous it's lies at Y-axis
Answer:
$486
Step-by-step explanation:
First you find the area of the window. The area of a square is equal to h×w, so we take 9×9 which equals 81. Since it costs $6 per square foot, we now take 81×6, which gives us an answer of $486.
I believe it is C. Multiply 640 by 7.5. You should get 4800
Answer:

Step-by-step explanation:
Given

Recursive: 
Required
Determine the formula
Substitute 2 for n to determine 


Substitute 


Next is to determine the common difference, d;



The nth term of an arithmetic sequence is calculated as

Substitute
and 


Hence, the nth term of the sequence can be calculated using