1/ -2020 + (1543 + 2020)

\(=-2020+1543+2020\)

\(=-2020+2020+1543\)

\(=0+1543\)

\(=1543\)
2/ (245 – 97) – 245

\(=245-97-245\)

\(=245-245-97\)

\(=0-97\)

\(=-97\)
3/ (-145) – (118 – 145)

\(=-145-118+145\)

\(=-145+145-118\)

\(=0-118\)

\(=-118\)
4/ (-36 + 89) - (145 + 89 – 36)

\(=-36+89-145-89+36\)

\(=\left(-36+36\right)+\left(89-89\right)-145\)

\(=0+0-145\)

\(=-145\)

học tốt

1/ -2020+(1543+2020)

=-2020+1543+2020

=(-2020+2020)+1543

=0+1543=1543

2/ (245-97)-245

=245-97-245

=(245-245)-97

=0-97=-97

3/ -145-118+145

=(-145+145)-118

=0-118=-118

4/ -36+89-145-89+36

=(-36+36)+(89-89)-145

=0+0-145=-145

1) - 7264 + ( 1543 + 7264 )

= ( - 7264 + 7264 ) + 1543

= 0 + 1543

= 1543

2) ( 144 - 97 ) - 144

= ( 144 - 144 ) - 97

= 0 - 97

= - 97

3) ( - 145 ) - ( 18 - 145 )

= ( - 145 + 145 ) - 18

= 0 - 18

= - 18

4) 111 - ( - 11 + 107 )

= ( 111 + 11 ) + 107

= 122 + 107

= 229

5) ( 27 + 514 ) - ( 486 - 73 )

= ( 27 + 73 ) + ( 514 - 486 )

= 100 + 28

= 128

6) ( 36 + 79 ) + ( 145 - 79 - 36 )

= ( 36 - 36 ) + ( 79 - 79 ) + 145

= 0 + 0 + 145

= 145

1) - 7264 + ( 1543 + 7264 )

= ( - 7264 + 7264 ) + 1543

= 0 + 1543

= 1543

2) ( 144 - 97 ) - 144

= ( 144 - 144 ) - 97

= 0 - 97

= - 97

3) ( - 145 ) - ( 18 - 145 )

= ( - 145 + 145 ) - 18

= 0 - 18

= - 18

4) 111 - ( - 11 + 107 )

= ( 111 + 11 ) + 107

= 122 + 107

= 229

5) ( 27 + 514 ) - ( 486 - 73 )

= ( 27 + 73 ) + ( 514 - 486 )

= 100 + 28

= 128

6) ( 36 + 79 ) + ( 145 - 79 - 36 )

= ( 36 - 36 ) + ( 79 - 79 ) + 145

= 0 + 0 + 145

= 145

a: \(-7264+\left(1543+7264\right)\)

\(=-7264+1543+7264\)

\(=\left(-7264+7264\right)+1543\)

=0+1543

=1543

b: \(\left(144-97\right)-144\)

\(=144-97-144\)

\(=\left(144-144\right)-97\)

=0-97

=-97

c: \(\left(-145\right)-\left(18-145\right)\)

\(=-145-18+145\)

\(=\left(-145+145\right)-18\)

=0-18

=-18

d: \(111+\left(-11+27\right)\)

\(=\left(111-11\right)+27\)

=100+27

=127

e: \(\left(27+514\right)-\left(486-73\right)\)

\(=27+514-486+73\)

\(=\left(27+73\right)+\left(514-486\right)\)

\(=100+28=128\)

f: \(\left(36+79\right)+\left(145-79-36\right)\)

\(=36+79+145-79-36\)

\(=\left(36-36\right)+\left(79-79\right)+145\)

=0+0+145

=145

tham khảo

1/ -7264 + (1543 + 7264)

= -7264 + 7264 + 1543

= 0 + 1543 = 1543

2/ (144 - 97) - 144

= 144 - 144 - 97

= 0 - 97 = -97

3/ -145 - (18 - 145)

= -145 + 145 - 18

= 0 - 18 = 18

4/ 111 + (-11 + 27)

= 111 - 11 + 27

= 100 + 27 = 127

5/ (27 + 514) - (486 - 73)

= 27 + 514 - 486 + 73

= 27 + 73 + 514 - 486

= 100 + 28

= 28

6/ (36 + 79) + (145 - 79 - 36)

= 36 + 79 + 145 - 79 - 36

= 36 - 36 + 79 - 79 + 145

= 145

7/ 10 - [12 - (-9 - 1)]

= 10 - (12 + 9 + 1)

= 10 - (12 + 10)

= 10 - 10 - 12

= -12

8/ (38 - 29 + 43) - (43 + 38)

= 38 - 29 + 43 - 43 - 38

= 38 - 38 + 43 - 43 - 29

= -29

9/ 271 - [(-43) + 271 -(-17)]

= 271 - (-43 + 271 + 17)

= 271 + 43 - 271 - 17

= 43 - 17 = 26

10/ -144 - [29 - (+144) - (+144)]

= -144 - 29 + 144 + 144

= -29 + 144

= 115

b: =144-97-144=-97

a) Tính bằng cách thuận tiện nhất:

134 x 4 x 5

= 134 x (4 x 5)

= 134 x 20 = 1680

5 x 36 x 2

= 36x (5 x 2)

= 36 x 10 = 360

42 x 2 x 7 x5

= (42 x 7) x (2 x5)

= 294 x 10 = 2940

b) 137 x 3 + 137 x 97

= 137 x (3 + 97)

= 137 x 100 = 13700

94 x 12 + 94 x 88

= 94 x (12 + 88)

= 94 x 100 = 9400

428 x 12 - 428 x 2

= 428 x (12 - 2) = 4280

537 x 39 - 537 x 19

= 537 x (39 - 19)

= 537 x 20 = 10740

\(\text{a) -72+ (154+76) }\)

\(=-72+230\)

\(=158\)

\(\text{b) (144-97) -144 }\)

\(=47-144\)

\(=-97\)

\(\text{c) -145- (-18-145) }\)

\(=-145-\left(-163\right)\)

\(=18\)

\(\text{d) 38-(12+13+14) }\)

\(=38-39=-1\)

\(\text{e)-144-(29-144-144) }\)

\(=-144-\left(-259\right)=115\)

\(-72+\left(154+74\right)\)

\(=\left(-72\right)+230\)

\(158\)

\(\left(144-97\right)-144\)

\(=47-144\)

\(=-97\)

\(-145-\left(-18-145\right)\)

\(=\left(-145\right)-\left(-163\right)\)

\(=18\)

\(38-\left(12+13+14\right)\)

\(=38-39\)

\(=-1\)

\(-144-\left(19-144-144\right)\)

\(=\left(-144\right)-\left(-259\right)\)

\(=115\)

[144 - 97] - 144

= 144 - 97 - 144

= 0 - 97

= -97

[-145] - [18 - 145]

= 145 - 18 + 145

= 0 - 18

= -18

111 + [-11 + 27]

= 111 - 11 + 27

= 100 + 27

= 127

(144-97)-144=144-97-144= -97

(-145)-(18-145)=(-145)-18+145=-18

111+(-11+27)=111-11+27=127

1)-7264+(1543+7264)=-7264+1543+7264=(-7264+7264)+1543=0+1543=1543

2) (144-97)-144=144-97-144=(144-144)-97=0-97=-97

3) -145-(18-145)=-145-8+145=(-145+145)-8=0-8=-8

4)111+(-11+27)=111-11+27=100+27=127

1) 1543

2) -97

3) -18

4) 127

Nhớ tick mình nha !!!!! Đúng 100% đấy!!!!!

-7264 + 1543 + 7264

= -5721 +7264

= 1543

144 -97 -144

= 144 - 144 - 97

=-97

-145 - 18 + 145

=-163 + 145

= -18

sorry cau cuoi to khong lam duoc

tick nha

Bài 1:

a) −x + 8 = −17

−x = −17 − 8

−x = −25

⇒ x = 25

Vậy x = 25

x = −2

c) x − 45 = −17

x = −17 + 45

x = 28

Vậy x = 28

d) |x + 1| = 20 (>0)

TH₁: x + 1 = 20       TH₂: x + 1 = −20

x = 20 − 1                        x       = −20 − 1

x = 19                              x       = −21

Vậy x∈\(\left\{-21;19\right\}\)

e) |x − 3| − 16 = −4

|x − 3| = −4 + 16

|x − 3| = 12 (>0)

TH₁: x − 3 = 12             TH₂: x − 3 = −12

x = 12+3                                x = −12 + 3

x = 15                                    x = −9

Vậy x∈\(\left\{-9;15\right\}\)

b) 35 − x = 37

x = 35 − 37

x = −2

Vậy x = −2

Bài 2: 

a) (144 − 97) − 144

= 144 − 97 − 144
= (144 − 144) − 97
= − 97

b) (−145) − (18 − 145)

= −145 − 18 + 145

= (−145 + 145) − 18

= −18

c) (27 + 514) − (486 − 73)

= 27 + 514 − 486 + 73

= (27 + 73) + (514 − 486)

= 100 + 28

= 128

d) (38 − 29 + 43) − (43 + 38)

= 38 − 29 + 43 − 43 − 38

= (−38 + 38) + (−43 + 43) − 29

= 0 + 0 − 29

= −29