Question

Help!!!! with question !!!

Answer 1

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

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

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=(a_(n+1))/(a_n)`

`r=(-11)/(5.5)=-2`

`a_1=5.5\\\\a_(n+1)=-2a_n`