**Special Equations**

The graph the equation
is a

vertical line thru (a,0),

The graph the equation
is a

,horizontal line thru (0,b)

**Special Equations**

Graph the equation y = 5

Graph the equation y = −2

Graph the equation x = 4

Graph the equation x = −7

Graph the equation y = −15

Graph the equation y =12

Graph the equation x = 14

Graph the equation x = −72

**The Slope of A Line **

The slope of a line is given by the ratio

The slope of the line containing the points

and is
given by

**Find the slope of the line shown below.**

Find the change in y and the change in x.

Find the change in and y the change in x.

Find the change in y and the change in x.

Find the change in y and the change in x.

Find the change in and y the change in x.

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Find the slope of the line thru

(3, 2) and (5,6 ).

Look at the graph of this line to see

that the is always 2 units.

Find the slope of the line thru

(2,3) and (6,5) .

Find the slopes of the lines thru

each of the ordered pairs .

(4,1) and (−2,−3)

(-2,4) and (6,−7)

(-10,3) and (−10,4)

(-1,3) and (−2,3)

Use your calculator to graph the following

equations using the standard window.

y = 0ยทx + 1

y = x +1

y = 2x +1

y = 3x +1

y = 4x +1

What effect does changing the value of m

in y = mx + 1 have on the graph of the

equation.

Use your calculator to graph the following

equations using the standard window.

y = −x +1

y = −2x +1

y = −3x +1

What does the graph of the line
y = mx + 1

look like if m is a negative value ?

Use your calculator to graph the following

equations using the standard window.

y = 2x + 0

y = 2x + 4

y = 2x −3

y = 2x −5

What effect does changing the value of b

in y = 2x + b have on the graph of the

equation.

The Slope- Intercept Equation

The equation y = mx + b is called

the slope- intercept equation .

The slope of the line is given by m.

The y-intercept is given by (0,b).

Find the slopes and y- intercepts of

each of the following :

Graph each of the following :

The Point-Slope Equation

Given the point and a slope m,

The point-slope equation of the line is given by

How do we get this equation?

Find the equation of the line thru

(3, 2) with slope 3.

y − 2 = 3( x −3)

y − 2 = 3x −9

y = 3x − 7

Find the point-slope equation of

the line thru (−2,1) with slope -2

the line thru (1,−1) with slope -5

the line thru with slope -1/2

Describe the graph of each equation.

y −1 = 2( x − 2)

y + 2 = −3( x +1)

Graph each equation.