Question

Help me Solve This:

Answer 1

4. Two ocean beaches are being affected by erosion. The table shows the width, in feet, of each beach at high tide measured where 1995 is represented by year 0.
Year number Western Beach width (in feet) Dunes Beach width (in feet)
0 100 20
5 90 45
10 80 70
11 78 75
12 76 80
15 70 95
5.
A. Describe the patterns shown by the erosion data measurements shown for each of the beaches in the table.
B. Between which years will the beaches have approximately the same width?
C. Assuming these rates remain constant, what can you do to get a better approximation of when the two beaches will have the same width?

Answer 2

if you know how to do this @mathmale thats awesome

Answer 3

What have you thought of doing so far?

Question: Which year is represented by '12'?

Answer 4

for every +10 width there is +25 width in Dunes but then its changes after 3

Answer 5

Focus on the first column in this table:

0 100 20
5 90 45
10 80 70
11 78 75
12 76 80
15 70 95

What do the figures in the first column represent? Which one represents the year 2007?

Answer 6

im not sure. 12?

Answer 7

yeah its 12

Answer 8

That '12' in the first column DOES represent 2007. I wanted to be certain that you understand the significance of the figures in the first column before we proceed.

Now, what do the figures in the 2nd column represent?

Answer 9

Western Beach width (in feet)

Answer 10

Right. Now, determine whether the width of Western Beach is increasing with time, decreasing or staying constant.

Answer 11

decreasing

Answer 12

Good. Look at the third column. Is the width of the other beach incr., decr. or constant?

Answer 13

increasing

Answer 14

second column is decreasing and 3rd is increasing

Answer 15

Good. So, we see that the width of one beach is incr. and that of the other is decr.

In which year are the widths of the two beaches closest to one another?

Answer 16

Still interested in solving this problem, ZW?

Answer 17

11

Answer 18

sry my screen froze

Answer 19

Which calendar year does '11' represent?

Answer 20

2006?

Answer 21

Please read "B. Between which years will the beaches have approximately the same width?" and answer this as best you can. What are you looking for here?

Answer 22

ZW: If you want further help in solving this problem, then please show effort and respond promptly. "woops" doesn't cut it as a serious answer. How would you answer the question, "B. Between which years will the beaches have approximately the same width?"

Answer 23

2006-2007?

Answer 24

^

Answer 25

or does it have to be more than 2 years

Answer 26

Yes, between 2006 and 2007, or between years 11 and 12.

Right.

Now move on to part C. Explain, as best you can, what this question is asking of you and how you might go about answering it.

Answer 27

em how can i tell when the next time the width will be near eachother again?? but they wont be near eachother again cuz one is increasing while the other is deceasing right?? trick question maybe?

Answer 28

You are correct in stating that the width of one beach is increasing while the other is decreasing. At some point in time the widths of the two beaches are equal, and that's between 2006 and 2007 (years 11 and 12).

The goal is to obtain a better approximation of WHEN the two beaches have the same width. For example, that time might be "June 2006."

One way of doing this would be to plot the points corresponding to the widths of the two beaches. You'd end up with two graphs that interset for x = some value between 11 and 12. This method will work whether or not your data represent straight lines or only approximately straight lines.

Answer 29

What are you going to do next to answer Part C?

Answer 30

im not to sure.... so the value of x would be a decimal/fraction?

Answer 31

or the month?

Answer 32

Keep in mind that we are ONLY estimating the time at which the two beach widths are equal.

Just graph the data and determine APPROX.

Answer 33

where (at what time) the two graphs intersect.

Answer 34

oh wait. we're looking for which much in between the two year they were the closest in width?

Answer 35

Exactly.

Answer 36

ah ok thanks for the help :D

Answer 37

You're welcome. Good luck!

Answer 38

ive been tryin to get this down for 2 days now xD

Answer 39

Glad to be able to help. appreciate your persistence!