Hey, I need this answer in by today. Please help me solve this and give a word by word explanation. Thanks!

185

Step-by-step explanation:

firstly you calculate all in brackets

(280+20)÷3

300÷3

100-15

85

now you calculate 10×5=50

2×50=100

85+100=185

so firstly deal with problem inside the brackets, then you got multiplication and division outside their brackets and finally get 85 +100 =185

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!

e^-kt = n/n0 = 0.79  

-kt = ln 0.79  

t = - ln 0.79/0.0001  

= 2357 years

step-by-step explanation: