Answer:

Step-by-step explanation:
A line in 2-dimensional space has the following general equation:

Where m is the slope of the line, and b just a number
the slope can be obtaine using th following formula:

The point 2 is the one with the smallest value for x, that is (-10,-7) and the Point 1 is any other that belongs to the line, in this case, (-5,-9)

Resulting that 
To find the other term we can use any other point, I prefer us the first one so...
We have the following equation:

Resulting that b=18
I just have to eval the point (-10,-7) in the equation stated at the beginning knowin that m was calculated previously.
Let x = number of adult tickets
Let 2x = number of student tickets.
So, x + 2x = 336
3x = 336
x = 112
They sold 112 adult tickets.
Answer:
<h2>No solution</h2>
Step-by-step explanation:

Divide the total the lake holds by the number of days:
400 million / 25 days = 16 million gallons per day.
10! / (!2 * 8!) = '10 choose 10 choose 8