Answer:
slope = -7.65 per month
Explanation:
given data
2007 price p1 = $432
2011 price p2 = $80
time t2 = 46 months
solution
we consider here starting time t1 = 0 when price $432
so here slope will be
slope = [tex]\frac{p2-p1}{t2-t1}[/tex] .....................1
put here value and we will get
slope = [tex]\frac{80-432}{46-0}[/tex]
slope = -7.65 per month