The common difference is 19-7 = 31-19 = 12, so this is an arithmetic sequence. The initial term (when n=1) is 7.
The explicit formula for the terms of an arithmetic sequence is
an = a1 + d(n-1)
where "a1" is the first term and "d" is the common difference. The formula that matches a1=7 and d=12 is
B. a(n) = 7+(n-1)·12
True. The answer is the product of 4 and a number plus another number.
D. 24
you can simplify it down to y^3/x^2 then you just plug in x and y.
