3-3+x^3+6x^3-3y-3-4x^3

3x³ - 3y - 3   or     3(x³ - y - 1)

Step-by-step explanation:

3 - 3 + x³ + 6x³ - 3y - 3 - 4x³

group like terms

= x³ + 6x³ - 4x³ - 3y + 3 - 3 - 3

add similar terms

= 3x³ - 3y - 3   or     3(x³ - y - 1)

3432532

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!