The answer is 3/8 because 3 out of the 8 don't have erasers.
Answer:
Factoring
Step-by-step explanation:

The slope is -2.5 because you subtract 2y from both sides, then add two to both sides, then divide both sides by 2 to isolate y
Step-by-step explanation:
slope is the rise over run
rise= X
run= Y
X/Y = slope
The two equations are

and

the first equation can be solved for x to be

next you can substitute x in the second equation

Distribute 4 to everything in the parentheses

combine like terms:

subtract 28 from both sides of the equation

divide both sides by -1.5

plug this in to the original equation of x+y=7

subtract 4 from both sides.

Final Answer: they bought 3 adult tickets and 4 student tickets
Hope this helps!