a) 2459 - [ 400 + 459 ] = 2459 - 859 = 1600

b) 435 x 25 + 76 x 435 - 435 = 435 x ( 25 + 76 - 1 ) = 435 x 100 = 43500

c) 35 x 49 + 51 x 36 = 35 x 49 + 51 x ( 35 + 1 ) = 35 x 49 + 51 x 35 + 51 = 35 x ( 49 + 51 ) + 51 = 35 x 100 + 51 = 3500 + 51 = 3551

-HT-

a) 2459 - [400 + 459]                                                    b) Mk chịu                              c) 35 x 49 + 51 x 36                                             

        = [2459 - 459] + 400                                                                                               = 35 x (49 + 51) x 36

        = 2000 + 400                                                                                                          = 35 x 100 x 36

        = 2400                                                                                                                    = 3500 x 36

                                                                                                                                       = 126000

a) \(\text{2459 - (400 + 459)}\)

\(\text{= 2459 - 859}\)

\(\text{= 1600}\)

b) \(435\times25+76\times435-435\)

\(=435\times\left(25+76-1\right)\)

\(=435\times100\)

\(=43500\)

c) \(35\times49+51\times36\)

\(=35\times49+51\times\left(35+1\right)\)

\(=35\times49+51\times35+51\)

\(=35\times\left(49+51\right)+51\)

\(=35\times100+51\)

\(=3500+51\)

\(=3551\)

a) 2459 - (400 + 459)

= 2459 - 400 - 459

= (2459 - 459) - 400

= 2400 - 400

= 2000

b) 435 x 25 + 76 x 435 - 435

= 435 x (25 + 76 - 1)

= 435 x 100

= 43500

c) 35 x 49 + 51 x 36

= 1715 + 1836

= 3551

a:1600

b:53500

c:1802

a) 2459 - ( 400 + 459 )

= ( 2459 - 459 ) - 400

= 2000 - 400

= 1600

b) 435 x 25 + 75 x 435

= 435 x ( 75 + 25 )

= 435 x 100

= 43 500

c) 35 x 49 + 51 x 35

= 35 x ( 49 + 51 )

= 35 x 100

= 3500

z mak p k bít uk

wá dễ

a) =1600

b) =43 500

c) =3500

a, 435*25+76*435-435

=435*(25+76-1)

=435*100

=43500

b, 35*49+51*36

=35*49+51*(35+1)

=35*49+51*35+51

=35*(49+51)+51

=35*100+51

=3500+51

=3551

\(a,435\times25+76\times435-435\)

\(=435\times\left(25+76-1\right)\)

\(=435\times100\)

\(=43500\)

\(b,35\times49+51\times36\)

\(=1715+1836\)

\(=3551\)

a) 435.25+76.435-435                                       b) 35.49+51.36

=435(25+76-1)                                                   =?????

=435.100                                                            ý b có sai đầu bài k đó bn ơi????

=43500            

\(\text{- ( 2789 _ 435 ) + ( 1789 _ 1435 )}\)

\(=-2789+435+1789-1435\)

\(=\left(-2789+1789\right)+\left(435-1435\right)\)

\(=-1000+-1000\)

\(=-2000\)

\(=-\left(-2010\right)+36.41-36.\left(-59\right)\)

\(=2010+36.\left(41+59\right)\)

\(=2010+36.100\)

\(=2010+3600\)

\(=5610\)

\(-75.\left(18-65\right)-65.\left(75-18\right)\)

\(=-75.18+75.65-65.75+65.18\)

\(=18.\left(-75+65\right)+75.\left(65-65\right)\)

\(=18.\left(-10\right)+75.0\)

\(=-180\)

\(-15:x=3\)

\(x=-15:3\)

\(x=-5\)

\(-3x+8=7\)

\(-3x=-1\)

\(x=\frac{1}{3}\)

\(\left(x-6\right).\left(7-x\right)=0\)

\(\Rightarrow\orbr{\begin{cases}x-6=0\\7-x=0\end{cases}\Leftrightarrow\orbr{\begin{cases}x=6\\x=7\end{cases}}}\)

\(\Rightarrow x\in\left\{6;7\right\}\)

\(2.\left(x-3\right)-3.\left(x-5\right)=4.\left(3-x\right)-18\)

\(2x-6-3x+15=12-4x-18\)

\(2x-3x+4x=12-18-15+6\)

\(3x=-15\)

\(\Rightarrow x=-5\)

\(-a.\left(c-d\right)-d.\left(a+c\right)=-c.\left(a+d\right)\)

\(-a.c+a.d-d.a+-d.c=-c.\left(a+d\right)\)

\(-c.\left(a+d\right)+a.\left(d-d\right)=-c.\left(a+d\right)\)

\(-c.\left(a+d\right)+a.0=-c.\left(a+d\right)\)

\(\Rightarrow-c.\left(a+d\right)=-c.\left(a+d\right)\)

(3a+2).(2a–1)+(3–a).(6a+2)–17.(a–1)

=6a²−3a+4a−2+18a+6−6a²−2a−17a+17

=(6a²−6a²)+(−3a+4a+18a−2a−17a)+(17−2+6)

=0+0+21

=21

học tốt

(4 x 25 x 8) +( 4 x 37 x 8) + (2 x 36 x 16)

= 3136

hok tốt !

(4 x 25 x 8) +( 4 x 37 x 8) + (2 x 36 x 16)

= 3136

nhanh mà

1. 36 x 25 x 4

= 36 x 100

= 3600

2. 18 x 24 : 9

= 18 : 9 x 24

= 2 x 24

= 48

3. 41 x 2 x 8 x 5

= 41 x 8 x 10

= 328 x 10

= 3280

4. 108 x (23+7)

= 108 x 30

= 3240

5. 215 x 86 + 215 x 14

= 215 x (86+14)

= 215 x 100

= 21500

6. 53 x 128 - 43 x 128

= (53-43) x 128

= 10 x 128

= 1280

=3 giúp mìn nha