Transcript Graphing Linear equations…

Warm ups (HW will get stamped tomorrow)
Complete the given ordered pairs of the following equation:
y = 4x + 2
(-3,?)
(?,0)
(4,?)
(?,5)
5-4 Graphing Linear
Equations
Objective: To identify a linear
equation and graph linear
equations.
Graphing Linear equations…
Without a domain!! Dun dun dunn….
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What if we don’t give you the domain?
How will you pick good numbers?
Solve for y
Logic – pick whole #s
At least 3 points
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Why?
Example 1
Graph y = 3x – 1
x
y
Example 2
Graph y = 1x – 4
2
x
y
Example 3
Graph x + 2y = 6
x
y
2 Special Cases
Only x
Only y
x + 2 = -3
x = -5
(-5, __)
You can plug in any number for y,
x will always be -5. Vertical line!!
2y = 8
y=4
(__, 4)
You can plug in any number for x,
y will always be 4. Horizontal line!!
Linear equation:
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Something that can be written in standard form
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Ax + By = C
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A is always positive
Change to Ax + By = C
Standard Form
4x = 7 + 2y
-2y
- 2y
4x – 2y = 7
y = 4x – 1
-4x -4x
-4x + y = -1
-1(-4x + y = -1)
4x – y = 1
TOO
1. x + 3 = 2y + 5
x – 2y = 2
2. y + 10 = 5
y = -5
3. 5x + 2x = y - 5
7x – y = -5
Not Linear Equations
An equation is not linear if:
1. The variable has an exponent
3x2 – 4y = 0
2. The variable is in the denominator of a fraction
3 + 4y = 4
x
3. The variables are being multiplied together
3xy = 4
Linear Equations
Is it a linear equation? If so, write in standard
form. If not, why?
No:
1. 3 + y = 2
x 4
2. x - 2y = 5
5
Denominator
Exponent
multiply
3. 3y + 2 = 0
4. 8x - 7y = 2x - 5
5. 4x2 – 3x = y
6. 5xy = 30
Homework
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Pg. 283 # 16-27, 29, 32, 35, 36, 37, 42