Question

Help!!!! with question !!!

Answer 1

Answer:

$\large\boxed{A)\ 5.5\ and\ -44}$

$\large\boxed{B)\ a_1=5.5,\ a_{n+1}=-2a_n}$

Step-by-step explanation:

A)

If a, b and c are a geometric sequence, then ac = b².

We have:

x, -11, 22, y, 88, -176

Therefore

$22x=(-11)^2$

$22x=121$        divide both sides by 22

$x=5.5$

and

$-176y=88^2$

$-176y=7744$             divide both sides by (-176)

$y=-44$

B)

Find the common ratio:

$r=\dfrac{a_{n+1}}{a_n}$

$r=\dfrac{-11}{5.5}=-2$

$a_1=5.5\\\\a_{n+1}=-2a_n$