Hi Andres,
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Coordinates:
(6,12) and (3,21)
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Slope:
Formula:
Solution:
Slope: -3
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Compute the y intercept:
Use: y = mx + b
y = (-3)x + b
12 = (-3) x 6 + b
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Isolate b:
(-3) x 6 + b = 12
-3 x 6 + b = 12
-18 + b = 12
b = 30
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Slope Intercept Form:
Follow y = mx + b
m = slope
b = y intercept
Answer: y = -3x + 30
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Point Intercept Form:
Formula: y - y1 = m(x - x1)
m = slope
y1 and x1 = first coordinate set.
m = -3
y1 = 12
x1 = 6
Answer: y - 12 = -3(x - 6)
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Part B:
Approximately for every day he spends delivering he spends a 2.1 minutes on it per day. Well, the reason I say this is because on the chart it says he spends 10 days. When you multiply 10 and 2.1 you get 21!
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Hope This Helps :)