The school store has 1200 pencils in stock and sells an average of 25 pencils per day. The manager reorders when the the number of pencils in stock is 650. In how many days will the manager have to reorder? Write an equation that can be used to determine in how many days the manager will have to reorder.

hello from mrbilldoesmath!

answer:

25x^2 + 90x + 84

discussion:

mn(x) = m(n(x)) = m( 5x + 9) =

(5x + 9)^2 + 3 =>

25x^2 + 90x + 9^2 + 3 =

25x^2 + 90x + 84                 (as 9^2 = 9*9 = 81)

which is the second choice

regards,  

mrb

p.s.   i'll be on vacation from friday, dec 22 to jan 2, 2019. have a great new year!

      2

  2 is to go somewhat to the top right of a because it is squared    

v= a h/3