(2) Writing Equations of Lines Notes Theo.notebook
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(2) Writing Equations of Lines Notes Theo.notebook September 27, 2021 change in y change in x rise run distance over time remember: FORMULAS a ratio comparing one quantity to another ratio of the change in y coordinate to the change in x coordinate y 2 y 1 x 2 x 1 m= Rate of Change Slope = =
Transcript of (2) Writing Equations of Lines Notes Theo.notebook
(2) Writing Equations of Lines Notes Theo.notebook September 27, 2021
change in ychange in x
riserun
distance over timeremember:
FORMU
LAS
a ratio comparing one quantity to another
ratio of the change in y coordinate to the change in x coordinate
y2 y1x2 x1
m=
Rate of Change
Slope
= =
(2) Writing Equations of Lines Notes Theo.notebook September 27, 2021
Don't forget:
Finding Slope from Points
1. label the first coordinates x1 and y12. label the second coordinates x2
and y23. Substitute and simplify
(6,3), (7,4) (2,5), (7,8)
y2 y1x2 x1
m=
(2) Writing Equations of Lines Notes Theo.notebook September 27, 2021
Finding Slope from a Table
1. subtract the ys2. subtract the xs3. divide y difference/x difference
Or pick two points and use y2 y1x2 x1m=
x y3 11 30 5... ...4 13
x y4 20 24 2
x y5 35 15 1
m= m= m=
Determine the Slope and yIntercept
Given: Slope Intercept Form
slope:
Yintercept:
Slope is # infront of x
yintercept is # added and is (0, ?)
ex. y = 3x 5 y = x + 9
slope:
Yintercept:
slope intercept form
y = mx + b
(2) Writing Equations of Lines Notes Theo.notebook September 27, 2021
Graphing a Line
1. Make a point at the yintercept (0,b)
2. From the point move up and over the slope and make a point where you finish
3. Connect the points with a straight line
y = x +125(0,4) m= 3
Let's practice!
Board Work!
(2) Writing Equations of Lines Notes Theo.notebook September 27, 2021
Line Am = = =
Line Bm = = =
Line Dm = = =
Line Em = = =
Line Fm = = =
Line Cm = = =
E
A
3
13
1
31
31
3
a
bc
d
a. The slope of a is m=
b. The slope of b is m =
c. The slope of c is m =
d. The slope of d is m=(yards)
(seconds)
Running in an obstacle course
e. Interpret and explain a possible scenario of what was happening during the obstacle course by looking at the slopes of the lines.
2. Use the graph of the speed a competitor was running during an obstacle course, to answer questions ae.
Homework: 3.5 Slope Name:________ Determine the Slope for each line. Write it as a faction two different ways and as a decimal.
1. subtract the ys2. subtract the xs3. divide y difference/x difference
Or pick two points and use
y2 y1x2 x1m=
x y3 151 30 32 15
x y4 24 54 74 0
x y5 5020 505 50
m= m=m=
(2) Writing Equations of Lines Notes Theo.notebook September 27, 2021
Finding Slope from Points1. label the first coordinates x and y2. label the second coordinates x and y3. Substitute and simplify
(5,4), (7,4)(13,5), (9,6)
y2 y1x2 x1
m=
y2 y1x2 x1
m=
(2,3), (2,8) (1,3), (2,8)
1) 2)
3) 4)
Examples: Write the y intercept and
the slope (in 3 ways) for each line.
y = 2/3 x 5 y = 3/5x 3
y = 4x + 3 y = 7/6 x 8
(2) Writing Equations of Lines Notes Theo.notebook September 27, 2021
1) 2)
3) 4)
y = 2/3 x 5 y = 3/5x 3
y = 4x + 3 y = 7/6 x 8
Graph each equation using slope and y intercept.
(2) Writing Equations of Lines Notes Theo.notebook September 27, 2021
Given a Table or Graph
y = mx + b
Need slope, need yintercept
Given a Table or Graph
(2) Writing Equations of Lines Notes Theo.notebook September 27, 2021
