64 Writing Linear Equations in SlopeIntercept Form

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6-4 Writing Linear Equations in Slope-Intercept
Form

• Master Shires

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Real Life Situation with Linear Equations

• Jessie and Bob have agreed to mow lawns this
  summer. Jessies agreement with his neighbor is
  that he be paid 10 in the beginning and then 5
  per week to mow the grass. Bobs agreement was
  that he made 7 every week that he mowed his
  aunts lawn. Write a table of how much each
  earned for the first 10 weeks of summer. Can you
  write an equation for how much each earned?

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Summer income
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Definition

• Given the slope m and the y-intercept b of a
  line, the slope-intercept form of an equation of
  the line is y mx b
• (It cant be easier. Just put the slope where m
  is, and put the y-intercept where b is.)
• (Yes, the x and the y will stay right where they
  are.)

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An Easy One

• Write the slope-intercept form for a line that
  has the slope 3 and the y-intercept 8.
• Hmmm.. Go aheaddo it yourself.
• y 3x 8
• Good job!

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Kick it up half a notch

• Write the equation if the slope is and the
  y-intercept is -5

• Tricky, tricky.
• y x - 5

You are all too good.
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Another Notch!!

• Write the equation in slope-intercept form of the
  line 4x - 3y 6.
• Ahhhhhh.
• Wait, you can do this.what is the key?

• SLOPE!!! Then, find it. (m )

• Next, find your y-intercept.
• Cover up the x term.
• Put it all in order
• y x - 2

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Maybe should have told you before

• Ax By C is Standard Form
• m
• y-intercept
• x-intercept

• But it was a lot more fun figuring it out on your
  own.
• Wasnt it?

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Do you remember direct variation?

• Direct variation is y kx
• What if we just changed one of the letters,
  likek intoidkm?
• Then we would have y mx
• Look familiar at all?

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Homework

• 350 19-45 odd