Lesson 9

For each graph, calculate the slope of the line.

Match each pair of points to the slope of the line that joins them.

Draw a line with the given slope through the given point. What other point lies on that line?

1. Point A, slope = $\text-3$
2. Point A, slope = $\frac {\text{-}1}{4}$
3. Point C, slope = $\frac {\text{-}1}{2}$
4. Point E, slope = $\frac {\text{-}2}{3}$

Suppose you wanted to graph the equation $y=\text-4x-1$.

1. Describe the steps you would take to draw the graph.
    
2. How would you check that the graph you drew is correct?
    

Write an equation for each line.

A publisher wants to figure out how thick their new book will be. The book has a front cover and a back cover, each of which have a thickness of $\frac{1}{4}$ of an inch. They have a choice of which type of paper to print the book on.

1. Bond paper has a thickness of $\frac{1}{4}$ inch per one hundred pages. Write an equation for the width of the book, $y$, if it has $x$ hundred pages, printed on bond paper.
2. Ledger paper has a thickness of $\frac{2}{5}$ inch per one hundred pages. Write an equation for the width of the book, $y$, if it has $x$ hundred pages, printed on ledger paper.
3. If they instead chose front and back covers of thickness $\frac{1}{3}$ of an inch, how would this change the equations in the previous two parts?