Which is the equation of a parabola with focus -2,-4 and vertex -4,-4

 Scott to deliver his packages = 30 times and -3 is his delivery time decrease per day.

Explanation: Since the line passes from the two points (3,21) and (6,12)-

as we know that the equation of a line passes through two points and is   ×

Thus equation of the line is ×(x-3)

= y-21=-3(x-3)

=y-21= -3 x+9

3 x +y=30, Which is the expression of Scott's delivery times on different days.

since according the graph- y-intercept= 30, which is the times in which Scott delivering his product initially.

Now, we have to find out Scott's delivery time decrease per day, for this slope of line 3x+y=30  is, m =

m= =-3

so required answer is,  slope=-3