
Quadratic formula is

'a' is the coefficient of x^2 = 4
'b' is the coefficient of x = 2
'c' is the constant = -1
Now we plug in all the values in quadratic formula



The above one is the substitution of values of a,b,c in quadratic formula.
Answer: $287.50
Step-by-step explanation:
Find out how much each ticket costs: 57.50/3= 19.17
Multiply that by 15: 19.7x15=287.5
Distribute on the left
217+111x-185=-4
Combine like terms
111x+32=-4
Sybtract 32 from both sides
111x=-36
Divide both sides by 111
x= -36/111
x=-12/37
Final answer: x=-12/37
Your height to the problem would 18mm you would just take 612/34=18