Answer:
First option: 
Second option: 
Fourth option: 
Step-by-step explanation:
Rewrite each equation in the form
and then use the Discriminant formula for each equation. This is:

1) For
:

Then:
Since
this equation has no real solutions, but has two complex solutions.
2) For
:

Then:
Since
this equation has no real solutions, but has two complex solutions.
3) For
:

Then:
Since
this equation has one real solution.
4) For
:
Then:
Since
, this equation has no real solutions, but has two complex solutions.
Answer:
Total number of chairs in the restaurant = 160.
Step-by-step explanation:
Total number of tables in the restaurant = 50
It is given that 40% of the tables have 2 chairs at each table.
40% of 50 = 
= 20
So, 20 tables have 2 chairs at each table.
Number of chairs required for 20 tables = 20 × 2 = 40
Remaining 60% of the tables have 4 chairs at each table.
60% of 50 = 
= 30
So, 30 tables have 4 chairs at each table.
Number of chairs required for 30 tables = 30 × 4 = 120
Hence, total number of chairs in the restaurant = 40 + 120 = 160.
1.125 as a decimal. The reason is because I asked a computer