Answer:
a₇ = 2.375
Step-by-step explanation:
There is a common ratio r between consecutive terms, that is
r =
=
=
= - 
This indicates the sequence is geometric with nth term
= a₁ 
where a₁ is the first term and r the common ratio
Here a₁ = 152 and r = -
, then
= 152
, so
a₇ = 152
= 152 ×
= 2.375
Answer: y=0,5x²-x-1,5.
Step-by-step explanation:

We summarize (1) and (3):

Substitute b=-1 into (2):

From (5) subtract (4):

Substitute a=0,5 into (4):

Hense:
y=0,5x²-x-1,5.