Evaluate the expression for the given value of the variable(s). -x2 - 4x; x = –3

  3

Step-by-step explanation:

There are a significant number of minus signs here. We can simplify it a bit by factoring out -x:

  = -x(x +4)

When we substitute x = -3, we get ...

  = -(-3)(-3 +4)

  = 3(1)

  = 3

x+14

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!