Answer:
Since both terms are perfect squares, factor using the difference of squares formula.
(x+9y)(x−9y)
I believe it would be 13p im not for sure though
Answer:
22.5
Step-by-step explanation:
You can just take 450 calories divided by 20 ounces. 450 divided by 20 is 22.5, so that is the answer.
I think the answer is A because it I'm right it did double the size.
Answer: 
<u>Step-by-step explanation:</u>
Note the following identities: tan² x = sec²x - 1

tan² x + sec x = 1
(sec² x -1) + sec x = 1
sec² x + sec x - 2 = 0
(sec x + 2)(sec x - 1) = 0
sec x + 2 = 0 sec x - 1 = 0
sec x = -2 sec x = 1
