Pyramid Surface Area = (½ * Perimeter of Base * Slant Height) + Base Area
Base perimeter = 4 * 18 = 72 inches
Base Area = 18*18 = 324 square inches
Pyramid Surface Area = (.5 * 72 * 12) + 324
Pyramid Surface Area = 432 + 324
Pyramid Surface Area = 756 square inches
Source:
http://www.1728.org/volpyrmd.htm


Positive sine, negative tangent, means we have a negative cosine. We're talking about the second quadrant.



We know it's negative,

Answer: -(1/3)√5
Answer:

Step-by-step explanation:
Just subtract the two because x + y = z and z-x = y

You can test this by adding this expression back to the original.

Answer:
That is a rectangular prism
Step-by-step explanation:
Because I'm smart