Lesson Two

WARM UP Speed (m/s) Time (s)

In your spiral notebook, write down as many real life examples of slope as you can.

The diagram at the right shows the side view of a ski lift. 1.What is the vertical change from: a. A to B? b.B to C? c.C to D? 2.What is the horizontal change from: a.A to B? b.B to C? c.C to D 3.Find the ratio of the vertical change to the horizontal change for each section of the ski lift. 4.Which section is the steepest? 10 feet 40 feet 10 feet 30 feet A 1 B 4 C 1 B 3 C 3 D 3 = ; = ; = B to C

The Magnum Cedar Point, OH Ghost Rider Knott’s Berry Farm Xcelerator Knott’s Berry Farm Superman 6 Flags Magic Mountain Son of Beast King’s Island, OH How steep is the steepest roller coaster? These are completely vertical!

Imagine a roller coaster moving from LEFT to RIGHT

There are four different kinds of slope the coaster could encounter...

And 2 Special Cases… The zero- fun coaster The impossibly scary coaster What kind of slope are they?

That’s a really scary coaster, so the slope is…

Aw! That’s zero fun!

For the following slides, call out whether the slope is positive, negative, zero, or undefined. Wait for the count of 3 before you say your answer!

positive

undefined

negative

zero

How do you calculate the slope of a line? 1. Pick two points on the line. 2. Calculate “rise over run”. 3. Determine the sign.

Start with 2 points on gridline intersections Step 1:

How do you calculate the slope of a line? OR... Slope = Vertical change Horizontal change m Rise Run Slope = m Rise Run Step 2:

What sign is it? Look to see if the slope is increasing Or decreasing Show me! Step 3:

Model # 1: Watch me do the three steps Step 1: Choose 2 points Rise = 2 Run = 1 Rise Run 2 1 m = 2 Step 3: Determine the sign positive Slope = Rise Run Step 2: +

Model # 2: Watch me do the three steps Step 1: Choose 2 points Rise = 1 Run = 3 Rise Run 1 3 m = 1/3 Step 3: Determine the sign negative Slope = Rise Run Step 2: -

Find the slope of this line Rise = 1 Run = 3 Rise Run negative

Practice # 3: Find the slope of this line Rise Run Rise = 3 Run = 2 +

Tell your partner... What are the steps to find the slope of a line from a graph? Calculate rise over run. Look at the line to see if the slope is positive or negative.

Classwork Work with your partner to complete the worksheet. Find the slope of the line by using RISE over RUN. Write the slope down next to graph. You may want to draw in the rise and run.

The constant rate of change of a line is called the slope of the line.

Types of slope: positive slope negative slope undefined slope zero slope

dependent variable “Y” independent variable “X” The “y” value depends on the “x” value.