Answer:
0.875 is equivalent to 7/8
Leave a thanks if this helped
5/11 = 18/y
5 y = 18 · 11
5 y = 198
y = 198 : 5
y = 39.6
So first we assume that half is adult and have is student.
So
215 adult 215 student
Now since it said they were 70 less student tickets than adult tickets we subtract 70.
215 - 70 = 145
Now we add the 70 we subtracted from student tickets to the adult tickets.
215 + 70 = 285
So there were
285 adult tickets sold and 145 student tickets sold
I hope this helped. Have a great day!
ANSWER

EXPLANATION
The quadratic equation is:

Group variable terms:

Add the square of half, the coefficient of y to both sides.


The LHS us now a perfect square trinomial:

Take square root:


The first choice is correct.