The dimensions of a rectangle are StartRoot 50 a cubed b squared EndRoot and StartRoot 200 a cubed EndRoot. A student found the perimeter as follows: 2 StartRoot 50 a cubed b squared EndRoot + StartRoot 200 a cubed EndRoot = 2 times 5 a b StartRoot 2 a EndRoot times 10 a StartRoot 2 a EndRoot. = 10 a b StartRoot 2 a EndRoot + 20 a StartRoot 2 a EndRoot. = 30 a b StartRoot 2 a EndRoot. What is the students error?

i believe that is true.

step-by-step explanation:

hope my answer has you if not i'm sorry.

0.84 dang lotta people are looking for this lol or if you round up its 1 but the overall answer to that is 0.84

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

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