the formula is a_{1}+(n-1) d
so a_{1} would be the first number in the sequence, which would be 13 in problem 9.
13+(n-1)d
then you put in n, which is 10 (it represents which number in the sequence you're looking for, for example 16 is the second number in the sequence)
13+(10-1)d
then you find the difference between each number, represented by d which in this case is 3
13+(10-1)3
13+(9)3
13+27=
40
Answer:
6
Step-by-step explanation:
Because 6 is 6 times as 1, 12 is 6 times as 2, 18 is 6 times as 3 and so on.
Answer:

Real part = 3 & imaginary part = 1
2) 4 + 7i - 8 = 4 -8 + 7i
= -4 + 7i
Real part = -4 & imaginary part = 7


Real part = -2 & imaginary part = -5

b) 1) 6 + 4i
2) -12+ 5i
3) 5-14i