Delana also bought 3 bags of pencils with 12 pencils in each bag.When the party began, she found that 13 of the pencils were bro
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Answer:
Step-by-step explanation:
The directrix y=-6 is parallel to the x axes, so parabola has equation of the form
where is the vertex of parabola and p is parabola's parameter.
By the definition, is the distance from the vertex to the directrix, so
Hence, the equation of parabola is
See attached diagram for the graph of parabola and its directrix.
In vertex form this equation is
Given:
$7/child
$10/adult
Total people = 700
Total money = $6,400
First, make two equations.
Let a = # of adults & Let c = # of children.
Let p = total people
1. a+c = 700
2. 10a+7c = 6,400
Then, rearrange the equation to solve for a variable.
c = 700-a
Substitute (700-a) for c, or the # of children in the second equation.
10a+(700-a) = 6400
9a+700 = 6400
9a+700-700 = 6400-700
9a = 5700
9a/9 = 5700/9
a = 633
= # of adults attended
700-633 = c = 66 
= # of children attended
$7/child
$10/adult
Total people = 700
Total money = $6,400
First, make two equations.
Let a = # of adults & Let c = # of children.
Let p = total people
1. a+c = 700
2. 10a+7c = 6,400
Then, rearrange the equation to solve for a variable.
c = 700-a
Substitute (700-a) for c, or the # of children in the second equation.
10a+(700-a) = 6400
9a+700 = 6400
9a+700-700 = 6400-700
9a = 5700
9a/9 = 5700/9
a = 633
700-633