Tính bằng cách hợp lý nhất:

\(a)\)\(-64.159+136.\left(-8\right)^2+123.64\)

\(=64.\left(-159\right)+136.64+123.64\)

\(=64.\left(-159+123+136\right)\)

\(=64.100\)

\(=6400\)

\(b)\)\(84.\left(16-37\right)-16.\left(37+84\right)\)

\(=84.16-84.37-16.37-16.84\)

\(=84.\left(16-16\right)-37.\left(84+16\right)\)

\(=84.0-37.100\)

\(=0-3700\)

\(=-3700\)

a) 19 x 64 + 76 x 34 = 19 x 64 + 19 x 4 x 34 = 19 x (64 + 4 x 34) = 19 x 200 = 3800

b) 35 x 12 + 65 x 13 = 35 x 12 + 65 x 12 + 65 = 12 x (35 + 65) + 65 = 12 x 100 + 65 = 1265

c) 136 x 68 + 16 x 272 = 136 x 68 + 16 x 2 x 136 = 136 x (68 + 16 x 2) = 136 x 100 = 13600

cái này làm sao tính nhah đc

a) 19 x 64 + 76 x 34 = 19 x 64 + 19 x 4 x 34 = 19 x (64 + 4 x 34) = 19 x 200 = 3800

b) 35 x 12 + 65 x 13 = 35 x 12 + 65 x 12 + 65 = 12 x (35 + 65) + 65 = 12 x 100 + 65 = 1265

c) 136 x 68 + 16 x 272 = 136 x 68 + 16 x 2 x 136 = 136 x (68 + 16 x 2) = 136 x 100 = 13600

a) 3800

b) 1265

c) 13600

a) 19 . 64 + 76 .34 = 38. 32 + 38 . 68
                                  = 38 . (32 + 68) = 38 .100 = 3800
b) 35 . 12 + 65 . 13 = 35 . 12 + 65 . (12 + 1)
                                   = 35 . 12 + 65 . 12 + 65 = 12 . (35 + 65) + 65
                                   = 1200 + 65 = 1265.
c) 136 . 68 + 16 . 272 = 136 . 68 + 32 .136
                                       = 136 . (66 + 32) = 136 . 100 = 13600

k mik nha!

\(a,19\times64+76\times34.\)

\(=38\times32+38\times68\)

\(=38\times\left(68+32\right)\)

\(=38\times100\)

\(=3800\)

\(b,35\times12+65\times13\)

\(=35\times12+65\times\left(12+1\right)\)

\(=35\times12+65\times12+65\)

\(=12\times\left(35+65\right)+65\)

\(=12\times100+65\)

\(=1265\)

\(c,136\times68+16\times272\)

\(=136\times68+32\times136\)

\(=136\times\left(32+68\right)\)

\(=136\times100\)

\(=13600\)

Bài 1: 

a) =25,97+(6,54+103,46)

=25,97+110

=135,97

b)136x75+75x64

=75x(136+64)

=75x200

=15 000

c) (21/8+1/2):5/16

=(21/8+4/8)x16/5

=25/8x16/5

=10

d)3/17-4/5+14/17

=(3/17+14/17)-4/5

=1-4/5

=1/5

Bài 2:

a)720:\([41-(2x-5)]\)=120

              41 - (2x-5)                 =720:120

              41 - (2x-5)                 =6

                      2x-5                   =41-6

                      2x-5                   =35

                      2x                      =35+5

                      2x                      =40

                      x                        =40:2

                      x                        =20

b)2/3 x X +3/4=3

   2/3 x X        =3-3/4

   2/3 x X        =12/4-3/4

   2/3 x X        =9/4

             x        =9/4:2/3

             x        =9/4x3/2

             x        =27/8

c) x+0,34=1,19x1,02

    x+0,34=1,2138

    x         =1,2138-0,34

    x         =0,8738

\(\frac{\left(-4\right)^x}{64}=-16\)

\(\Leftrightarrow\left(-4\right)^x=64.16\)

\(\Leftrightarrow\left(-4\right)^x=1024\)

\(\Leftrightarrow4^x=1024\)

\(\Leftrightarrow4^x=4^5\)

\(\Rightarrow x=5\)

\(\frac{\left(-4\right)^x}{64}=-16\)

\(\Leftrightarrow\left(-4\right)^x=64.16\)

\(\Leftrightarrow\left(-4\right)^x=1024\)

\(\Leftrightarrow4^x=1024\)

\(\Leftrightarrow4^x=4^5\)

\(\Rightarrow x=5\)

Vậy \(x=5\)

ko ghi đề

\(=25,97+\left(6,54+103,46\right)\)

\(=25,97+110\)

\(=135,97\)

a/135,97

b/1500

c/10

a.) 25,97 + 6,54 + 103,46

= 6,54 + 103,46 + 25,97

= 110 + 25,97

=135,97

b.)136 . 75 + 75 .64

= ( 136 + 64 ) . 75

= 200 . 75

= 15000

c.)