2.) Your parents drove 300 miles in 6 hours. At what speed (miles per hour) were they driving?

50 mph

Step-by-step explanation:

300 / 6 = 50

you can check this by setting up the equation,

6 x 50 = 300

So with this being said, you can conclude that your parents are driving a 50 miles per hour.

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!