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31 votes
The table shows the number of tickets, n, to a school play sold t days after the tickets went on sale. Find a quadratic model for the data WITHOUT the use of a calculater.

The table shows the number of tickets, n, to a school play sold t days after the tickets-example-1
User YoungDad
by
2.6k points

1 Answer

23 votes
23 votes

Answer

The quadratic model for this data

n = -2t² + 24t + 10

Step-by-step explanation

Quadratic functions are given as

y = ax² + bx + c

where y = n, t = x and a, b and c are constants.

n = at² + bt + c

when t = 1, n = 32

32 = a(1)² + b(1) + c

32 = a + b + c

when t = 3, n = 64

64 = a(3)² + b(3) + c

64 = 9a + 3b + c

when t = 4, n = 74

74 = a(4)² + b(4) + c

74 = 16a + 4b + c

Combining the three equations

a + b + c = 32

9a + 3b + c = 64

16a + 4b + c = 74

We can then solve this simultaneously and obtain that

a = -2

b = 24

z = 10

So, the quadratic model for this data

n = -2t² + 24t + 10

Hope this Helps!!!

User Eti
by
3.0k points
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