The 30/60/90 right triangle is the biggest cliche in trig. We recall the sides come in ratio 

First x:


Next y:


Choice C
Lets say the number of adult tickets is x. This means the number of student tickets is 2x. So, 2x + x = 285, or 3x =285. The means x = 95. So the number of adult tickets sold is 95.
Answer:
B
Step-by-step explanation:
tan45° = 10/x
=> 1 = 10/x
=> x = 10
=> y^2 = 10^2 + 10^2 = 200
=> y = 100*sqrt(2)
=> b