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E QUATION O F A L INE Slope – Intercept Form y = m + b x represents the of the lineslope m represents the y-value of the y-intercept, b ( 0, ) b

x y Let's look at an example--- The equation of this line is y=+x 2 6 y=+x mb m Slope  = 2 y-intercept  b  ( 0, ) 6

Let's try without the graph! The equation of this line is y=─x 3 4 y=+x mb m Slope  = 3 y-intercept  b  ( 0, ) − 4 + (−4)

− 4 3 Let's Graph It! The equation : y= ─ x 4 m Slope: = y-intercept: ( 0, )  We need a starting POINT  We need one more point to draw the line. Rise 3 Run 1  Now, just draw a line through the 2 points! 3  The equation gives that point! REMEMBER: SLOPE is the "rise over run" of 2 points on the line. 1  THAT'S IT! x y

4 3 Let's try another! The equation : y= + x 6 m Slope: = y-intercept: ( 0, ) What's our starting POINT 6  How do we find another point? Rise −3 Run 4  Now, just draw a line through the 2 points!  FANTASTIC! 4 − 3 − REMEMBER: Negative "rise" is down ? x y

S UMMARY Graphing the Equation Of A Line In Slope – Intercept Form y=+xmb  Use the as the starting y – intercept POINT  Use the to find the 2 nd point slope  Draw the line through the 2 points