Graphing Linear Equations by the slope-intercept method

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Graphing Linear Equationsbythe slope-intercept
method
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The slope-intercept equation
The slope-intercept equation of a line is y mx
b m is the slope of the line b is the
y-intercept (where the graph crosses the y-axis)
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Graph using slope-intercept
To use the slope-intercept equation of a line,
y mx b we must first solve for y
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Graph using slope-intercept
Step 1 Get the 2x to the other side of the
equal sign Hop and Swap If you cross the
equal sign, your sign changes! Hop across the
and swap your sign! 5y 2x 15
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Graph using slope-intercept
5y 2x 15 Step 2 To isolate the y, we must
now divide both sides of the equation by 5
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Graph
In this equation, the slope is The
y-intercept is 3
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Graph
In this equation, the slope is The
y-intercept is 3
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Graph
The first point we are going to graph is the
y-intercept
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The meaning of slope
Remember slope Slope tells us how to get from
one point to another on the line. If rise 2
and run 5 It means that if you rise 2
and run 5 youll be back on the line
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Graph
Up 2
Over 5
(0, 3)
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A reminder about fractions
These are all equivalent. Whenever I have a
negative fraction, I use the rule negative
signs float Keeping the negative with the top
means that the top tells you how far up or
down The bottom is always over to the right
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When asked to graph the equation of a line by the
slope-intercept method

• Remember You must first solve the equation
  for y so you can use y mx b
• b is the y-intercept.
• m is the slope.
• Plot the y-intercept first.
• Use the slope ( ) to walk to the next
  point.