# How do you find the geometric means in the sequence 9,__ ,__ ,__,144?

Jun 5, 2017

See explanation.

#### Explanation:

In the geometric sequence we have:

${a}_{1} = 9$, ${a}_{5} = 144$.

We can write that:

$9 \cdot {q}^{4} = 144$

${q}^{4} = 16$

$q = 2 \vee q = - 2$

From those calculation we can deduce that the sequence can be:

$9 , 18 , 36 , 72 , 144$ or $9 , - 18 , 36 , - 72 , 144$