Question 1037673
{{{P(t) = 67.35 - 3t/8}}}
First, write this in y=mx+b form. In that case, m is the slope, and b is the Y-intercept. 

{{{P(t)=-3t/8+67.35}}}

Now, you can just read off the slope and Y-intercept from this equation:

{{{slope = -3/8}}}
{{{y-intercept = 67.35}}}

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Good Luck,
tutor_paul@yahoo.com