Answer:

Step-by-step explanation:
The complete question in the attached figure
we have

we know that
(ab)(x) is equal to the product of a(x) and b(x)
so

Applying distributive property



This is a quadratic equation
The other expressions not produce a quadratic equation
Answer:
Step-by-step explanation: 85 students and 80 adults
Answer:
240 minutes
Step-by-step explanation:
If it's 40 minutes for just 5 papers, we need to figure how many minutes it would take to grade just 1. So you have to divide 40 by 5 which is 8. Then 8 time 30 which is 240.
You have to convert millimeters in meters, 1000 mm = 1 m,
6000 mm = 6 m
6 m is your answer.