\(a)\)

\(\left(-31\right)+\left(50-19\right)-\left(150-31\right)\)

\(=\left(-31\right)+50-19-150+31\)

\(=\left(-150\right)-19\)

\(=-169\)

\(b)\)

\(25.\left(45-17\right)-45.\left(25-17\right)\)

\(=25.45-25.17-45.25+45.17\)

\(=0\)

\(c)\)

\(\frac{-1}{12}+\frac{4}{3}=\frac{5}{4}\)

\(d)\)

\(3+\frac{-5}{20}+\frac{30}{75}+\frac{-7}{4}\)

\(=\left(\frac{3}{5}+\frac{30}{75}\right)-\left(\frac{5}{20}+\frac{7}{4}\right)\)

\(=1-2\)

\(=-1\)

a) (-31)+(50-19)-(150-31)

= (-31)+50+(-19)-150+(-31)
= (-31)+50-150+(-19)-(-31)
= (-31)+(-100)+12
= -119
b) 25(45-17)-45(25-17)
= 25.45-25.17-45.25-45.17
= 25(45-45)-25(17-17)
= 0
c) -1/12 + 4/3
= -1/12 + 16/12
= 15/12
= 5/4
d) 3/5+(-5)/20+30/75+(-7)/4
= 45/75+30/75+(-5)/20+(-35)/20
= 1+(-2)
= -1

1) = (8/31 + 23/31)+ ( -12/25+-13/25) = 1 + (-1) = 0
2) = 1/2 +3/4 -3/4 + 4/5 = 1/2 +4/5 = 13/10

3)= ( 7/3 x 15/21) x ( -5/2 x 4/-5 ) = ( 7/3 x 5/7 ) x 2 = 5/3 x 2 = 10/3

4) = 1/4 + 3/4 x -7/6 = 1/4 + -7/8 = -5/8

5)= 3/29 x 29/3 - 1/5 x 29/3 = 1 x 29/15 = 29/15

6)= 5/7 x ( 5/11 + 2/11 - 14/11) = 5/7 x -7/11 = -5 /11 

7) = 11/12 x -1/8 + 11/12 x -3/16  - 11/12 = 11/12 x ( -1/8 + -3/16 - 1) = 11/12 x -21/16 = -77/64 ( mk ko chắc , bạn ấn máy tính để thử lại )

8) = 203/20 - 7/4 + 41/13 = 198/20 + 41/13 = 99/10 + 41/13 = 1697/130 ( câu này cứ lỏ lỏ kiểu gì ý :v ) 

1) = (8/31 + 23/31)+ ( -12/25+-13/25) = 1 + (-1) = 0
2) = 1/2 +3/4 -3/4 + 4/5 = 1/2 +4/5 = 13/10

3)= ( 7/3 x 15/21) x ( -5/2 x 4/-5 ) = ( 7/3 x 5/7 ) x 2 = 5/3 x 2 = 10/3

4) = 1/4 + 3/4 x -7/6 = 1/4 + -7/8 = -5/8

5)= 3/29 x 29/3 - 1/5 x 29/3 = 1 x 29/15 = 29/15

6)= 5/7 x ( 5/11 + 2/11 - 14/11) = 5/7 x -7/11 = -5 /11 

7) = 11/12 x -1/8 + 11/12 x -3/16  - 11/12 = 11/12 x ( -1/8 + -3/16 - 1) = 11/12 x -21/16 = -77/64 ( mk ko chắc , bạn ấn máy tính để thử lại )

8) = 203/20 - 7/4 + 41/13 = 198/20 + 41/13 = 99/10 + 41/13 = 1697/130 ( câu này cứ lỏ lỏ kiểu gì ý :v ) 

a) \(27\cdot75+25\cdot27-150\cdot2023^0\)

\(=27\cdot\left(75+25\right)-150\cdot1\)

\(=27\cdot100-150\)
\(=2700-150\)

\(=2550\)

b) \(3^x+3^{x+1}+16\cdot4=2^2\cdot5^2\)

\(\Rightarrow3^x+3^x\cdot3=100-64\)

\(\Rightarrow3^x\cdot\left(1+3\right)=36\)

\(\Rightarrow3^x\cdot4=36\)

\(\Rightarrow3^x=36:4\)

\(\Rightarrow3^x=9\)

\(\Rightarrow3^x=3^2\)

\(\Rightarrow x=2\)

a) 27.75 + 25.27 - 150.2023⁰

= 27.(75 + 25) - 150.1

= 27.100 - 150

= 2700 - 150

= 2550

b) 3ˣ + 3ˣ⁺¹ + 16.4 = 2².5²

3ˣ.(1 + 3) + 64 = 4.25

3ˣ.4 + 64 = 100

3ˣ.4 = 100 - 64

3ˣ.4 = 36

3ˣ = 36 : 4

3ˣ = 9

3ˣ = 3²

x = 2

a) \(31\cdot72+\left(-31\right)\cdot70-2\cdot70\)

\(=31\cdot72-31\cdot70-2\cdot70\)

\(=31\cdot\left(72-70\right)-2\cdot70\)

\(=31\cdot2-2\cdot70\)

\(=2\cdot\left(31-70\right)\)

\(=2\cdot-39\)

\(=-78\) 

b) \(25\cdot\left(32+17\right)-32\cdot\left(25+47\right)\)

\(=25\cdot32+25\cdot17-32\cdot25-32\cdot47\) 

\(=25\cdot\left(32-32+17\right)-32\cdot47\)

\(=25\cdot17-32\cdot47\)

\(=425-1504\)

\(=-1079\)

các bạn ơi xin các bạn tội ngiệp cho tôi vài lik eSky Nguyễn

a).

= 27. (75+25)- 150

= 27. 100 -150

= 2700    - 150

= 2550

\(\dfrac{-6}{25}+\left|\dfrac{-4}{5}\right|-\left|\dfrac{2}{25}\right|\)

\(=\dfrac{-6}{25}+\dfrac{4}{5}-\dfrac{2}{25}\)

\(=\dfrac{-6}{25}+\dfrac{20}{25}-\dfrac{2}{25}\)

\(=\dfrac{12}{25}\)

b) \(\dfrac{5}{9}-\left|\dfrac{4}{9}\right|+\left|\dfrac{8}{5}\right|\)

\(=\dfrac{5}{9}-\dfrac{4}{9}+\dfrac{8}{5}\)

\(=\dfrac{1}{9}+\dfrac{8}{5}\)

\(=\dfrac{5}{45}+\dfrac{72}{45}\)

\(=\dfrac{77}{45}\)

a, 47.69-31(-47)

=47(69+31)

=47.100

4700

b,(-14)(-25)+25(-11)

=14.25+25(-11)

=25(14-11)

=25.3=75