Atrain traveling 50 mph left a station 30 minutes before a second train running at 55 mph. how soon did the second train overtake the first? if 50x represents the distance the slower train travels, then the faster train travels55(x - 0.5)55(x + 0.5)50 + 30x

idk this answer sorry cant on this one.

step-by-step explanation:

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

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