Answer: y = 3x+18
Slope = 3
Y intercept = 18
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Work Shown:
m = slope
m = (y2-y1)/(x2-x1)
m = (0-(-9))/(-6-(-9))
m = (0+9)/(-6+9)
m = 9/3
m = 3 ... is the slope
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y = mx+b
y = 3x+b .... plug in the slope
-9 = 3(-9)+b ... plug in the point (x,y) = (-9,-9)
-9 = -27+b
-9+27 = -27+b+27 .... adding 27 to both sides
18 = b
b = 18 ... is the y intercept
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We found that m = 3 is the slope and b = 18 is the y intercept
y = mx+b turns into y = 3x+18