Algebra 5.4

5.4 The Slope Formula

Learning Targets

Language Goal Students will be able to verbally

explian how to find slope.Math Goal Students will be able to find slope

using the slope formula.Essential Questions What is the important information

we can get from finding the slope?

5.4 Warm-up

5.3 Homework Check

5.3 Homework Check

Slope Formula

The letter m represents slope!

Need: Two points on a line to determine slope

Formula:

Example 1: Positive Slope Rises Find the slope of a line passing through(-3, 0) and (-1, 6)

Example 2: Negative Slope FallsFind the slope of the line passing through (-2, 1) and (1, -3)

Example 3: Positive or Negative?Find the slope of the line passing through (5, 0) and (0, 2)

Example 4: Zero Slope (Horizontal)

Find the slope of the line passing through (-1, -3) and (5, -3)

Example 5: Undefined Slope (Vertical)

Find the slope of the line passing through (0, -1) and (0, 4)

Notecard Slope

On your notecard write an ordered pair (x, y).

Your x and y coordinate may contain any number between -10 and 10.

Fractions are allowed too. Once it is written on your notecard

wait until further instructions.

Notecard Slope

You will partner with someone in the class

Use your two points to determine the slope of the line.

Once you have found your slope determine whether your slope is positive, negative, no slope or undefined.

We will rotate as a class.

Example 6: Given Slope, find y –coordinate

Find the vale of y so that the line passing through the points (-3, y) and (1, 5) has a slope of -2.

Example 7: Given Slope, find y –coordinate

Find the vale of y so that the line passing through the points (3, y) and (5, 8) has a slope of 2.

Example 8: Finding Slope from Tables

First, use the table to write two ordered pairs.

Then, use those two points to calculate slope using the slope formula.

Example 8: Finding Slope from Tables

x 0 2 5 6

y 1 5 11 13

Find two ordered pairs from the table.

Use the ordered pairs to calculate slope.

Example 8: Finding Slope from Tables

x -2 0 2 4

y 3 0 -3 -6

Find two ordered pairs from the table.

Use the ordered pairs to calculate slope.

Example 8: Finding Slope from Tables

x -2 0 2 4

y 3 0 -3 -6

Find two ordered pairs from the table.

Use the ordered pairs to calculate slope.

Example 9: Finding Slope from an Equation

Step 1: Find the x – intercept

Step 2: Find the y – intercept

Step 3: Use the slope formula

Example 9: Finding Slope from an Equation

Find the slope of the line described by

Example 9: Finding Slope from an Equation

Find the slope of the line described by

Whiteboards with LQ

Pass out Whiteboards or students can do in notebook.

Go over as a class.

5.4 Lesson Quiz