a) (−27). 1011 − 27. (−12) + 27. (−1)

= (-27). (1011 - 12 + 1)

= (-27). 1000 = -27 000

b) (−9). (−9). (−9) + 103 + 9.3

= (-9). 3 + 103 + 9.3

= 9.3 - 9.3 + 103

= 0 + 103 = 103

c) (−157). (127 − 316) − 127. (316 − 157)

= (-157). 127 - 316. (-157) - 127.316 - 127. (-157)

= (-157). 127 + 316. 157 - 127. 316 + 127.157

= (127.157 - 157.127) + (316. 157 - 127.316)

= 0 + (157 - 127). 316

= 0 + 30. 316

= 9480

a) (-27).1011-27.(-12)+27.(-1)

= -27.1011 +27.12+27.(-1)
= 27.(-1011)+27.12+27.(-1)

= 27.(-1011+12-1)

= 27.(-1000)

=-27000

c) (-157)(127-316)-127(316-157)

= (-157).127+157.316-127.316+127.127

= 316.(157-127)

= 316.30

= 9480

a, \(\left(29-9\right).\left(-9\right)+\left(-13-7\right).21\)

\(=20.\left(-9\right)+\left(-20\right).21\)

\(=-180+\left(-420\right)\)

\(=-600\)

a) (29 – 9). (-9) + (-13 – 7). 21

= 20. (-9) + [- (13 + 7). 21]

= 20. (-9) + (-20). 21

= (-20). 9 + (-20). 21

= (-20). (9 + 21)

= (-20). 30

= - (20. 30)

= - 600.

b) (-157). (127 – 316) – 127. (316 – 157)

= (- 157). 127 + (-157). (-316) + (–127). 316 + (-127). (-157)

= -157. 127 + 157. 316 – 127. 316 + 127. 157

= [- (127. 157) + 127. 157] + (157. 316 – 127. 316)

= 0 + 316. (157 – 127)

= 316. 30

= 9 480.

⇔127-(2x+9)³=2

⇔(2x+9)³=125

⇔(2x+9)³=5³

⇒2x+9=5

⇔2x=-4

⇔x=-2 

Vậy x=-2

a: \(=168:\left[180-\left(36+2^3\cdot8\right)\right]=168:80=\dfrac{21}{10}\)

b: =62-81-12+59-9

=50+50-81

=100-81

=19

c: \(=298\cdot198-298\cdot127+198\cdot127-198\cdot298\)

=127x(-100)=-12700

=144 : 6 + 127 - 114

=36 + 127 - 114

=163 - 114

=49

16x9:6+127-114

=144:6+13

=24+13

=37

Ok hk tot

so sánh hả

a, 3.7.23 - 21.(-17)

= 21.23  + 21.17

= 21.(23 + 17)

= 21.40

= 840

b, 7.6.3 - 7.[(-34) + 18)]

= 7.18 - 7.18 + 34.7

= 34.7

= 238

c, 71.64 + 32.(-7) - 13.32

= 71. 32 . 2 - 7.32 - 32. 13

= 32.(71.2 - 7 - 13)

= 32. (142 - 20)

= 32.122

=  3904

d, 13.(23 - 17) - 13.(23 + 17)

= 13.23 - 13.17 - 13.23 - 13.17

= (13.23 - 13.23) - (13.17 + 13.17)

= - 2.13.17

= - 26.17

= -442