a) 4.25-12.5+170:10

=100-60+17

=40+17

=57

b) (7+3³:3²).4-3

=(7+3).4-3

=10.4-3

=40-3

=37

c) 12:{400:[500-(125+25.7)]}

=12:{400:[500-(125+175)]}

=12:{400:[500-300]}

=12:{400:200}

=12:2

=6

d) 168+{[2.(2⁴+3²)-256⁰]:7²}

=168+{[2.(16+9)-1]:49}

=168+{[2.25-1]:49}

=168+{[50-1]:49}

=168+{49:49}

=168+1

=169

hepl me :(

chiều nay mình phải nộp rồi

\(23\left(x-1\right)+19=65\)

           \(23\left(x-1\right)=65-19\)

           \(23\left(x-1\right)=46\)

                    \(x-1=46:23\)

                    \(x-1=2\)

                            \(x=2+1\)

                           \(x=3\) 

     \(5x+3x=88\)

  \(x\left(5+3\right)=88\)

         \(x.8=88\)

            \(x=88:8\)  

            \(x=11\)

\(x^3=64\)

\(x^3=4^3\)

\(\Rightarrow x=4\)

    \(\left(5x-4\right):7-2=6\)

            \(\left(5x-4\right):7=6+2\)

             \(\left(5x-4\right):7=8\)

                      \(5x-4=8.7\)

                       \(5x-4=56\)

                                \(5x=56+4\) 

                                 \(5x=60\)

                                    \(x=60:5\)

                                    \(x=12\)

\(x^{50}=x\)

\(\Rightarrow x=1\)

\(4.2^x-3=125\)

        \(4.2^x=125+3\)

        \(4.2^x=128\)

            \(2^x=128:4\)

            \(2^x=32\)

            \(2^x=2^5\)

\(\Rightarrow x=5\)

k mk nha

a) = -19

b) = 325

c) = -682

d) = 34

a ) [ 25 + ( -15 ) ] + ( -29 ) = -19

b ) 512 - ( -88) - 400 - 125 = 75

c ) -(-310 ) + ( -210 - 907 + 125 )= - 682

d ) 2004 - ( 1975 ) - ( 2000 ) + 2005= 34

hok tốt .

a,[ 25 + ( -15 ) ] + ( -29 )

= 10 + ( -29 )

= -19

b, 512 - ( -88 ) - 400 - 125

= [ 512 - ( -88 ) ] - 400 - 125

= 600 - 400 - 125

= 200 - 125 

= 75

c, - ( -310 ) + ( -210 - 907 + 125 )

= 310 + ( -210 - 907 +125 )

= 310 + ( -1117 + 125 )

= 310 + ( - 992 )

= - 682

 d, 2004 - ( 1975 ) - ( 2000 ) + 2005

= 2004 - 1975 - 2000 + 2005 

= ( 2004 - 1975 ) - 2000 + 2005

= 29 - 2000 + 2005

= ( -1971 ) + 2005

= 34

  Bài 7 :

a) 3⁸: 3⁴ + 2² x 2³

=3^8-4 + 2²⁺³

=3⁴ + 2⁵

=81 + 32

=113

b) 3 x 4² - 2 x 3

=3 x 16 - 2 x 3

=48 - 6

=42

c)  Hình như sai đề nha bạn

d) Đề thiếu gì đó. Bạn kiểm tra lại nha

                                         Bạn kiểm tra lại đề nha 

c)4⁶.3⁴.9⁵:6¹²

=(2.2)⁶.3⁴.(3.3)⁵:(2.3)¹²

=2⁶.2⁶.3⁴.3⁵.3⁵:2¹²:3¹²

⁼2¹².3¹⁴:2¹²:3¹²

=3²=9

e)45³.20⁴.18²:180⁵

=(5.9)³.(2.10)⁴.(9.2)²(9.20)⁵

⁼5³.9³.2⁴.10⁴.9².2²:9⁵:20⁵

⁼5³.9³.2⁴.10⁴.9².2²:9⁵:2⁵:10⁵

⁼5³.2:10

=125.2:10

=250:10=25

=151-8+33=151+25=176