Find the missing term of the following geometric sequence. It could be the geometric mean or its opposite. 9, ___, 4, ...

Answer 1

A geometric sequence means you multiply one term by a number ("r") to get to the next term:

So 9r² = 4

r² = 4/9

r = ± 2/3

Using r = 2/3, 9•(2/3) = 6

Using r = -2/3, 9•(-2/3) = -6

Answer 2

can solve this way

9/x=x/4 is how a geometric sequence is defined (ratio same a_n/a_n+1=a_n+1/a_n+2)

x=+/-6