91Ó°ÊÓ

Explain the difference between linear interpolation and linear extrapolation.

Name the following form of the equation of a line: \(y-y_{1}=m\left(x-x_{1}\right)\)

Draw a scatter plot of the data. State whether x and y have a positive correlation, a negative correlation, or relatively no correlation. If possible, draw a line that closely fits the data and write an equation of the line. $$ \begin{array}{|c|c|} \hline x & y \\ \hline 1 & 2 \\ \hline 2 & 9 \\ \hline 3 & 8 \\ \hline 4 & 1 \\ \hline 5 & 4 \\ \hline 6 & 8 \\ \hline \end{array} $$

Suppose that bike rentals cost \(\$ 4\) plus \(\$ 1.50\) per hour. Write an equation to model the total cost \(y\) of renting a bike for \(x\) hours.

Write an equation of the line that is parallel to the given line and passes through the point. $$y=-3 x-3,(-4,-3)$$

Suppose that bike rentals cost \(\$ 4\) plus \(\$ 1.50\) per hour. Use the equation to find the cost of renting a bike for 12 hours.

BANKING Christina has her savings in a bank account. She withdraws \(\$ 8.25\) per week from her account. After 10 weeks, the balance is \(\$ 534 .\) Write an equation that models the balance \(y\) of Christina's account in terms of the number of weeks \(x .\) Do not consider any interest earned by the account.

Draw a scatter plot of the data. Draw a line that corresponds closely to the data and write an equation of the line. $$ \begin{array}{|c|c|} \hline x & y \\ \hline 3.0 & 9.9 \\ \hline 3.5 & 9.7 \\ \hline 3.7 & 8.6 \\ \hline 4.0 & 8.1 \\ \hline 4.0 & 8.4 \\ \hline 4.5 & 7.4 \\ \hline \end{array} $$

Write the equation in standard form with integer coefficients. $$y=3 x-8$$

Use the table which shows the average tuition for attending a private and a public four-year college. $$ \begin{array}{|c|c|c|}\hline \text { Year } & \text { Public college } & \text { Private college } \\\\\hline 1990 & \$ 2,035 & \$ 10,348 \\\\\hline 1991 & \$ 2,159 & \$ 11,379 \\\\\hline 1992 & \$ 2,410 & \$ 12,192 \\\\\hline 1993 & \$ 2,604 & \$ 13,055 \\\\\hline 1994 & \$ 2,820 & \$ 13,874 \\\\\hline 1995 & \$ 2,977 & \$ 14,537 \\ \hline 1996 & \$ 3,151 & \$ 15,581 \\\\\hline\end{array} $$ Write a linear model of the tuition for attending a public and of the tuition for attending a private college.