which type of function describes her total savings after m months and why?
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Answer:
A.
Step-by-step explanation:
I would advise finding the difference between 300 and 200 and 450 and 300:
[tex]300-200=100\\450-300=150[/tex]
We can eliminate C and D since she saves 100 the first month and 150 the second month.
The next step would be to find the increase every month:
[tex]\frac{Final value}{initial value}=x\\\\\frac{300}{200}=1.5 \\\\\frac{450}{300} = 1.5[/tex]
If we would write the increase as a function, we would get:
[tex]y= 1.5x[/tex]
we can check this by substituting values:
[tex]y=1.5*200\\y=300\\\\\\y=1.5*300\\y=450[/tex]
An exponential function looks like this:
[tex]y= a^x[/tex]
A linear function looks like this:
[tex]y=mx+b[/tex]
Our m is 1.5, a linear increase by 150% and our b is 0, which can be written like:
[tex]y=1.5x+0\\y=1.5x[/tex]
Therefore our function resembles a linear function more than an exponential function, eliminating answer B.