Warm ups

1
Warm ups

• Answers
• 4/3
• 2/7
• -2
• Zero
• No slope

• Find the slope
• (2,1) (8,9)
• (7,-8) (14,-6)
• (-4,-1) (-2,-5)
• (4,1) (-4,1)
• (3,2) (3,-2)

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6-1 Slope

• Objective To find a missing coordinate given two
  points and the slope.

3
Example 1

• Find the missing coordinate (r)
• (-1,-3) (7, r) m ¾
• 3 r (-3)
• 4 7 (-1)
• 3 r 3
• 4 8
• 4(r 3) 3(8)
• 4r 12 24
• 4r 12
• r 3

x1 y1 x2 y2
m y2 y1 x2 x1
This is a proportion Cross multiply!
4
Example 2

• Find the missing coordinate (r)
• (-4,-1) (r, -5) m -2
• -2 -5 (-1)
• 1 r (-4)
• -2 -4
• 1 r 4
• -2(r 4) 1(-4)
• -2r 8 -4
• -2r 4
• r -2

x1 y1 x2 y2
m y2 y1 x2 x1
This is a proportion Cross multiply!
5
TOO

• Find the missing coordinate (r)
• (-2,r) (10,4) m -1/2
• -1 4 r
• 2 10 (-2)
• -1 4 - r
• 2 12
• 2(4 r) -1(12)
• 8 2r -12
• -2r -20
• r 10

x1 y1 x2 y2
m y2 y1 x2 x1
This is a proportion Cross multiply!
6
Example 3

• Find the missing coordinate (r)
• (12,r) (r,6) m 2
• 2 6 r
• 1 r 12
• 1(6 r) 2(r 12)
• 6 r 2r 24
• 6 3r 24
• 30 3r
• r 10

m y2 y1 x2 x1
x1 y1 x2 y2
This is a proportion Cross multiply!
Combine like terms
7
Homework

• Pg. 330 30-38
• Show all of your work ?

8
ZONK

• Lets the games begin!!