a,5.4^x + 4^{2 + x} = 336

= 5.4^x + 4^x. 4² = 336

= 5.4^x + 4^x . 16 = 336

=(5+16).4^x= 336

=21.4^x=336

→ 4^x=16

→4^x=4²

→x = 2

a, 571 + 216 + 129 + 124

=(571+129) + ( 216 + 124)

=700 + 340

=1040 

b,27.74 + 26.27 - 355

=1998 + 702 - 355

=2700 - 355

=2345

c,100:{250 :[450-(4.5³ - 2².25)]}

100:{250: [450 -( 4.125 - 4.25)]}

=100:{250: [450 - (500 - 100)]}

=100:{250:[450-400]}

=100:{250:50}

=100: 5

=20

a, số chia hết cho 2 là: 320;4914;90

b, số chia hết cho 5 là: 2315;320;90

c,số chia hết cho 3 là: 4914;90;543

d, số chia hết cho 2;3;5;9 là:90

Quy Nhon city is in the south of Viet Nam. It's got a population of about 268,000 in 2024. It's very modern and the people are really friendly. Ther are many good amusement parks, shopping malls and buildings here. Dak Nong,Gia Lai, Kom Tum and Dak Lak are some quite nice places not far Quy NHon city. I sometimes visit these cities for holidays, but Quy Nhon city is more interesting