# Need Help with a Exponential and Linear Problem

#### beachin

##### New member
Could someone assist me with this problem (showing work)?

Belinda wants to invest $1000. The table below shows the value of her investment under two different options for two different years: Number in Years 1 2 3 Option 1 1300 1690 2197 Option 2 1300 1600 1900 Part A: What type of function, linear or exponential, can be used to describe the value of the investment after a fixed number of years using option 1 and option 2? Explain your answer. (2 points) Part B: Write one function for each option to describe the value of the investment f(n), in dollars, after n years. (4 points) Part C: Belinda wants to invest in an option that would help to increase her investment value by the greatest amount in 20 years. Will there be any significant difference in the value of Belinda's investment after 20 years if she uses option 2 over option 1? Explain your answer, and show the investment value after 20 years for each option. (4 points) #### Subhotosh Khan ##### Super Moderator Staff member Could someone assist me with this problem (showing work)? Belinda wants to invest$1000. The table below shows the value of her investment under two different options for two different years:

Number in Years 1 2 3
Option 1 1300 1690 2197
Option 2 1300 1600 1900

Part A: What type of function, linear or exponential, can be used to describe the value of the investment after a fixed number of years using option 1 and option 2? Explain your answer. (2 points)

Part B: Write one function for each option to describe the value of the investment f(n), in dollars, after n years. (4 points)

Part C: Belinda wants to invest in an option that would help to increase her investment value by the greatest amount in 20 years. Will there be any significant difference in the value of Belinda's investment after 20 years if she uses option 2 over option 1? Explain your answer, and show the investment value after 20 years for each option. (4 points)

What are your thoughts?

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#### stapel

##### Super Moderator
Staff member
Could someone assist me with this problem (showing work)?
As you saw in the "Read Before Posting" thread that you read before posting, showing your work is your department.

Belinda wants to invest \$1000. The table below shows the value of her investment under two different options for two different years:

Number in Years 1 2 3
Option 1 1300 1690 2197
Option 2 1300 1600 1900

Part A: What type of function, linear or exponential, can be used to describe the value of the investment after a fixed number of years using option 1 and option 2? Explain your answer. (2 points)
You plotted the points, sketched a rough line that seems a good fit through the points, and... then what? Based on what you saw, what did you conclude? Straight line, or not straight line?

Part B: Write one function for each option to describe the value of the investment f(n), in dollars, after n years. (4 points)
Based on your type of function, chosen in part (A), what equations did you get? (When you answer this, please state whether you are supposed to be finding "exact" equations, or if you're using, say, a graphing calculator to do regression models.)

Part C: Belinda wants to invest in an option that would help to increase her investment value by the greatest amount in 20 years. Will there be any significant difference in the value of Belinda's investment after 20 years if she uses option 2 over option 1? Explain your answer, and show the investment value after 20 years for each option. (4 points)
Graph your two lines for your two models of the two Options. For the portion of the graph past t = 20, what do you see? What do you conclude?

Please be complete. Thank you!