Answer:

Step-by-step explanation:
Let

We factor 2 to obtain;

We factor the polynomial within the parenthesis by grouping.



We apply difference of two squares on the second factor: 

We now compare to;

It is now obvious that 
Answer:
a(4) = 15/4
Step-by-step explanation:
Here we're told that the first term is a(1) = 30 and that the common factor r = 1/2.
Thus, the geometric sequence formula specific to this case is
a(n) = 30(1/:2)^(n-1).
What is the fourth term? Let n = 4,
a(4) = 30(1/2)^(4-1), or a(4) = 30(1/2)^(3), or a(4) = 30(1/8) = 30/8, or, in reduced form,
a(4) = 15/4.
Answer: 10
Step-by-step explanation:
add 2.75 to 0