Question 824968: Let y (# dollars in your bank account) be a linear equation of x (# years since 1980). If you had $2500 in your account in 1986 and $4500 in 1994:
A. Write y as a function of x
B- how much were you saving each year?
C- how much will you have in 2006?
---I've tried many ways of doing this, but right now I am completely lost. Thank You!
Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website! The key is that it is a linear, or straight line
equation.
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(A)
If you are plotting y on the vertical axis
and x on the horizontal axis, then
you are given 2 points:
( 6, 2500 ) and ( 14, 4500 )
Note that 6 and 14 are years since 1980
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Use the general point-slope equation:






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(B)
In the first year,
change in y is


$250 is saved each year
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(C)
In 26 years, you will have:



$7,500
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check:
does the line go through ( 6, 2500 ) and ( 14, 4500 ) ?
( 6, 2500 )




OK




OK
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