The total cost for a bucket of popcorn and 4 movie tickets is $56. The total cost for the same size bucket of popcorn and 6 movie tickets is $80. The cost of a bucket of popcorn is $8. Which equation represents the relationship between y, the total
cost of the popcorn and movie tickets, and x, the number of movie tickets that are purchased?
y = 12x + 8
y = 12x - 8
y = 14x + 8
y = 14x - 8

y = 12x + 8

Step-by-step explanation:

You can come to this conclusion by plugging in the amount of tickets bought as x in each equation, making sure the the answer y is $56 if x = 4 and $80 if x = 6

if the eqn of the parabola is f(x) = (x-4)(x+2), we need to mult. this out to find the coordinates of the vertex.

then f(x) = x^2 + 2x - 4x - 8, and f(x) = x^2 - 2x - 8.

one way in which you can find the vertex is to calculate x = -b / (2a).   here, that comes to

        )

x = = 1.   f(1) = 1^2 - 2(1) - 8 = - 9.   vertex is at (1, -9).

        2(1) 

find another point on the curve:   let x=0, for which y=-8.   then (0, -8) is on the curve.   plot the vertex and this point and draw a smooth parabola thru both.

hope this