Answer:
B
Step-by-step explanation:
You simplify it using radicals.
Answer: a = 8
Step-by-step explanation:
Volume of a square based pyramid is given as
.
where a is the length of the side and h is the height.
Substituting into the formula , we have
V = 
128 =
/3
384=
X 6
Divide through by 6
384/6 = 
64 = 
Therefore :
a = 
a = 8
Answer:
-213
Step-by-step explanation:
3|3-5|^2-(-15)^2
3(4)-225
=12-225= -213
6x-9x-4=-2x-2
3x-4=-2x-2
3x+2x=-2+4
5x= 2
x=2/5
Answer: (D) 
Explanation:

Just a note on writing down these expressions: I recommend using parentheses whenever you can to avoid misinterpretation. An expression 1/x-1/y / 1/x+1/y could be interpreted by someone as 1/x-(1/y / 1/x)+1/y, which is a different thing.