- ( 73 ) + ( 44 - 94 + 27 ) + 94

= -73 + 44 - 94 + 27 + 94

=( -73 + 44 + 27 ) + ( -94 + 94 )

= -2 + 0 = -2

- 73 + ( 44 - 94 + 27 ) + 94

= - 73 + 44 - 94 + 27 + 94

= ( 94 - 94 ) + ( - 73 + 27 ) + 44

= 0 + ( - 46 ) + 44

= - 2

   12 x 85 + 35 x 182 - 35 x 94

= 12 x (35 + 50) + 35 x 182 - 35 x 94

= 12 x 35 + 12 x 50 + 35 x 182 - 35 x 94

= (12 x 35 + 35 x 182 - 35 x 94) + 12 x 50

= 35 x ( 12 + 182 - 94) + 600

= 35 x 100 + 6x 100

= 100x (35 + 6)

= 100 x 41

= 4100

80865

nhớ k nha

=1003x27 + 27x3x477 + 27x6x94 -(11+70)

=1003x27+27x1431 + 27x564 - 81

=27 x (1003+1431+564) - 81

=27 x 2998 -81

=80946 - 81

=80865

24.25+102.94-94-94

=4.25.6+94.(102-1-1)

=100.6+94.100

=100.(6+94)

=100.100

=10000

HT

dấu nhân là chữ x thường nha

Đáp án: (x,y)∈{(18,2),(−18,3),(2,−2),(−2,7)}(x,y)∈{(18,2),(−18,3),(2,−2),(−2,7)}

Giải thích các bước giải:

ĐKXĐ: x≠0x≠0

Ta có:

3x+y3=563x+y3=56

→93x+xy3x=56→93x+xy3x=56

→9+xy3x=56→9+xy3x=56

→2(9+xy)=5x→2(9+xy)=5x

→18+2xy=5x→18+2xy=5x

→5x−2xy=18→5x−2xy=18

→x(5−2y)=18→x(5−2y)=18

Vì x,y∈Zx,y∈Z

→(x,5−2y)→(x,5−2y) là cặp ước của 1818

Mà 5−2y5−2y luôn lẻ với mọi số nguyên ZZ

→(x,5−2y)∈{(18,1),(−18,−1),(2,9),(−2,−9)}→(x,5−2y)∈{(18,1),(−18,−1),(2,9),(−2,−9)}

→(x,2y)∈{(18,4),(−18,6),(2,−4),(−2,14)}→(x,2y)∈{(18,4),(−18,6),(2,−4),(−2,14)}

→(x,y)∈{(18,2),(−18,3),(2,−2),(−2,7)}

\(215\times94+215\times5+215\)
\(=215\times\left(94+5+1\right)\)
\(=215\times100\)
\(=21500\)

215 × 94 + 215 × 5 + 215

= 215 × ( 94 + 5 + 1 )

= 215 × 100

= 21500

428 x 12 - 428 x 2

= 428 x (12 - 2) = 4280

1: =66+34-73-27+99=99

2: =54-45+30-54-30+5=-40

3: =42-56+33-33+56-42=0

4: =50-47-50+18+47-18=0

5: =10-28+30-4=2-4+10=12-4=8

\(\text{1.-(-66)+34+(-73)-27+99}.\)

\(=66+34-73-27+99=100-100+99=-99.\)

\(\text{2.54-(45-30+54)-30+5}.\)

\(54-45+30-54-30+5=\left(54-54\right)+\left(-45+5\right)+\left(30-30\right)=-40.\)

\(\text{3.42-56+33-(33-56+42)}.\)

\(=42-56+33-33+56-42=\left(42-42\right)+\left(-56+56\right)+\left(33-33\right)=0.\)

\(\text{4.50-(47+50-18)+(47-18)}.\)

\(=50-47-50+18+47-18=\left(50-50\right)+\left(-47+47\right)+\left(18-18\right)=0.\)

\(\text{5.10-(28-30+4)}.\)

\(=10-28+30-4=10+30-20-8-4=20-12=8.\)

\(\text{6.-(-73)+(44-94+27)+94}.\)

\(=73+44-94+27+94=\left(73+27\right)+\left(-94+94\right)+44=100+44=144.\)

73/49 x 94/51 x 100/146 x 51/25 = 188/49