SOLUTION: In 2000, about 33.1 billion photos were printed from film and that number was declining at a rate of 1.1 billion per year. There were 2.8 billion digital photos printed or stored

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Question 62910: In 2000, about 33.1 billion photos were printed from film and that number was declining at a rate of 1.1 billion per year. There were 2.8 billion digital photos printed or stored in 2000 and that number was growing at a rate of 2.9 billion per year.
a) Write two equations that can be used to predict n, the number of filmed or digital photos, in billions, t years after 2000.
b) Use a graphing calculator to determine the year in which the numbers of filmed photos and digital photos are the same.

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
In 2000, about 33.1 billion photos were printed from film and that number was declining at a rate of 1.1 billion per year. There were 2.8 billion digital photos printed or stored in 2000 and that number was growing at a rate of 2.9 billion per year.
a) Write two equations that can be used to predict n, the number of filmed or digital photos, in billions, t years after 2000.
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For photos you have a point (0,33.1) and a slope= (1.1)
You need an equation:
n=(slope)t+b
33.1=1.1(0)=b
b=33.1
EQUATION:
n=1.1t+33.1 (n in billions)
---------------
For digital photos you have a point (0,2.8) and slope=2.9
EQUATION
n=2.9t+2.8 (n in billions)
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b) Use a graphing calculator to determine the year in which the numbers of filmed photos and digital photos are the same.
graph%28300%2C200%2C-10%2C20%2C-10%2C60%2C+2.9x%2B2.8%2C1.1x%2B33.1+%29
Intersection at (16.833333,51.616666..)
Cheers,
Stan H.