First let’s review 5.1 y = mx + b

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First let’s review 5.1 y = mx + b
Write the equation in slope-intercept form, given m = 3 ang b = (0,-2) Example m = 3, b = (0,-2) y = mx + b y = __ x + ___

Write the equation of the line in slope-intercept form.
b = (0,1) y = mx + b

Given this equation, what is the slope and y-intercept?
+2x x 3y = 2x + 15 m = 2/3 b = (0,5)

Review 5.2 Point-Slope Form

Write the equation of the line in point-slope form.
(0,3) Or you can use any point (3,2)

Given (2,3) and slope = -2, write the equation in SLOPE-INTERCEPT
This is the equation of the line in point-slope form!! Now leave your answer in slope- intercept form.

Given (-8,4) and slope = -3/2, write the equation in SLOPE-INTERCEPT
This is the equation of the line in point-slope form!! Now leave your answer in slope- intercept form.

5.3 Writing equations of a line given two points

Forms of a linear equation
Slope-intercept Form y = mx + b Point-Slope Form y – y1 = m(x – x1)

If given two points, First, find the slope using the slope formula.
(x1 , y1) and (x2 , y2) First, find the slope using the slope formula. Example contains (5, –8) and (2, 7) m = 15 –3 m = –5 m = 7 – -8 2 – 5

If given two points, Then use the slope and EITHER point to work
like the previous example. y – y1 = m(x – x1) y – 7 = – 5(x – 2) y – 7 = –5x + 10 m = –5, contains (5, –8) and (2, 7) y = –5x + 17

Writing an Equation Given Two Points
1. Calculate the slope of the line. 2. Select the form of the equation. a. Slope-intercept form b. Point-slope form 3. Substitute and/or solve for the selected form.

Writing an Equation Given Two Points
Given the two ordered pairs, write the equation of the line in point-slope form. Calculate the slope. or

Writing an Equation Given Two Points in point-slope form:

Same example: Writing an Equation Given Two Points in slope-intercept form.
Start by using point-slope form:

2.) Writing an Equation Given Two Points in slope-intercept form.
(-5,7) (2,-7) Start by using point-slope form:

EVERY ONE GET A COMMUNICATOR:
WITH A BLANK SIDE!!

3.) Writing an Equation Given Two Points in slope-intercept form.
(2,0) (-2,6) Start by using point-slope form:

4.) Writing an Equation Given Two Points in slope-intercept form.
(10,-5) (8,4) Start by using point-slope form:

5.) Writing an Equation Given Two Points in slope-intercept form.
(6,5) (-3,5) Start by using point-slope form: Horizontal line

6.) Writing an Equation Given Two Points in slope-intercept form.
(-2,-4) (-4,8) Start by using point-slope form:

7.) Writing an Equation Given Two Points in slope-intercept form.
(-6,6) (9,1) Start by using point-slope form:

NOW WHAT IF I GAVE YOU A GRAPH, TELL ME THE EQUATION OF THE LINE:
WHAT’S THE MAJOR DIFFERENCE BETWEEN THESE TWO GRAPHS: So creating an equation using slope-intercept form would NOT work!!! The one on the right does not have a CLEAN y-intercept!!

Create the equation of the line using two points on the line:
(-3,4) (5,8)