Step 1: List the data points you are using

Step 2: Create a scatter plot of the data with everything properly labeled. You may use your
calculator with TI-Connect, LoggerPro, an online calculator, Desmos or by hand on
graph paper.

Step 3: Without using your calculator or computer, find the equation of a sinusoidal curve
that matches the data. Be sure to show your work. Write the equation in the form of

Step 4: Use your calculator to find the equation of a sinusoidal curve that matches the data.
If necessary round numbers to four decimal places.

Step 5: Graph the data points, the equation found in step 2 and the equation found in step 3. Be
sure to properly label your graph. Graphs should be done on graph paper (use color
pencils to distinguish the data points and the two equations.), or using your calculator
and TI Connect (try to do something that will distinguish the data points and the two
equations), or the free trial SmartView (use color to distinguish the data points and the
two equations), Desmos or LoggerPro (LoggerPro allows you the option to use different
colors)

Step 6: If we assume that 00 represents midnight then using your equations found, determine the
height of the tide at 6:45 AM. How do the two equations compare?

Step 7: If we assume that 00 represents midnight then using your equations found, determine the
height of the tide at 10:30 AM. How do the two equations compare?

Step 8: If we assume that 00 represents midnight then using your equations found, determine the
height of the tide at 3:20 PM. How do the two equations compare?

Step 9: If we assume that 00 represents midnight then using your equations found, determine the
height of the tide at 8:10 PM. How do the two equations compare?

Step 10: Use your calculator and the graph of the two equations to determine the times for
high tide and low tide. How do the different equations compare? Be sure to distinguish
between the tides. If necessary round the times to the nearest minute.

St.martins