(627 - 138) : (x : 2) = 163     =>>>  489 : (x : 2) = 163    =>>>>>>x : 2 = 489 : 163 =3

=>>>>>>>>>>x = 3 . 2 = 6 . Vậy x=6 .......k nha

(627 - 138) : (X : 2) = 163

489 : (X : 2) = 163

(X : 2) = 489 : 163

X : 2 = 3

X = 3 x 2

X = 6 

Ta có:(627-138):x:2=163

=>489:x:2=163

489:x=163x2

489:x=326

x=489:326=1.5

1) (-6 - 2) . (-6 + 2) = -8 . (-4) = 32
2) 627 + 125 + (-627) + |-46| -21 = 125 + 46 - 21 = 150
3) (-25) + 30 + (-16) + 25 + (-4) = 30 + (-20) = 10
4) 75 - 5.(15 - 40) - (-60) = 75 - 75 + 80 + 60 = 140
5) |31 - 17| - |15 - 52| = |14| - |-37| = 14 - 37 = -23
6) 13 - 18 - (-42) - 15 = 13 - 18 + 42 - 15 = 22
3 bài sau hết kiên nhẫn rồi, thông cảm nhé.

7) 369.4.[(- 5) + 4. (-8) ]

=  1476 . [(-5) + (-32)]

=  1476 . -37

=  -54612

8)  + 8

=  8 + 8

= 16
9) 72 : (-6 . 2 + 4)

= 72 : (-12 + 4)

= 72 : (-8)

= -9

(627 - 138) : (x : 2) = 163

     489      : (x : 2) = 163

                    x : 2 = 489 : 163

                    x : 2 = 3

                    x      = 3 x 2

                    x      = 6

k mình nha

~Chúc các bạn học gioiỉ~

( 627  -  138 ) : ( X : 2 ) = 163

X : 2 = ( 627 - 138 ) : 163

X : 2 = 489 : 163

X : 2 = 3

X       = 3 x 2

X       = 6

( 627 - 138 ) : ( x : 2 ) = 163

489 : ( x : 2 ) = 163

x : 2 = 489 : 163

x : 2 = 3

x = 3 . 2

x = 6

vậy x = 6

= \(-37+54-70-163+246\)

\(=\left(-37-163\right)+\left(54+24\right)-70\)

\(=-200+78-70\)

\(=-200+\left(78-70\right)\)

\(=-200+8\)

\(=-192\)

thank you

3) \(\left(x+3\right)^2+\left(x-2\right)^2-2\left(x+3\right)\left(x-2\right)\)

\(=\left(x+3\right)^2-2\left(x+3\right)\left(x-2\right)+\left(x-2\right)^2\)

\(=\left[\left(x+3\right)-\left(x-2\right)\right]^2\)

\(=\left(x+3-x+2\right)^2\)

\(=5^2=25\)

4) \(\left(3x-5\right)^2-2\left(3x-5\right)\left(3x+5\right)+\left(3x+5\right)^2\)

\(=\left[\left(3x-5\right)-\left(3x+5\right)\right]^2\)

\(=\left(3x-5-3x-5\right)^2\)

\(=\left(-10\right)^2\)

\(=100\)

câu a là hằng đẳng thức luôn

A=(2x+4)^2

B khai triển tung tóe ra thì phần sau triệt tiêu hết còn 4(a^2+b^2+c^2)

câu c cảm giác sai đề vì mấy câu này phải là (3x)^ ms ra hdt chứ nhỉ

MK ĐANG CẦN GẤP Ạ AI NHANH MK SẼ VOTE Ạ

a: Ta có: \(\left(3x-1\right)^2-2\left(5x-2\right)^2-2\left(x^2+x-1\right)\left(x-1\right)\)

\(=9x^2-6x+1-2\left(25x^2-20x+4\right)-2\left(x^3-x^2+x^2-x-x+1\right)\)

\(=9x^2-6x+1-50x^2+40x-8-2\left(x^3-2x+1\right)\)

\(=-41x^2+34x-7-2x^3+4x-2\)

\(=-2x^3-41x^2+38x-9\)

b: Ta có: \(\left(3a+1\right)^2+2\left(9a^2-1\right)+\left(3a-1\right)^2\)

\(=\left(3a+1+3a-1\right)^2\)

\(=36a^2\)

a) \(\left(2x+3\right)\left(x-4\right)+\left(x+5\right)\left(x-2\right)=\left(3x-5\right)\left(x-4\right)\)

\(\Leftrightarrow2x^2-8x+3x-12+x^2-2x-5x+10=3x^2-12x-5x+20\)

\(\Leftrightarrow2x^2-8x+3x-12+x^2-2x+10=3x^2-12x+20\)

\(\Leftrightarrow3x^2-7x-2=3x^2-12x+20\)

\(\Leftrightarrow-7x+12x=20+2\)

\(\Leftrightarrow5x=22\)

\(\Rightarrow x=\dfrac{22}{5}\)

tick cho mk nha

b) \(\left(8x-3\right)\left(3x+2\right)-\left(4x+7\right)\left(x+4\right)=\left(2x+1\right)\left(5x-1\right)\)

\(\Leftrightarrow24x^2+16x-9x-6-4x^2-23x-28=10x^2+3x-1\)

\(\Leftrightarrow20x^2-16x-34-10x^2-3x+1=0\)

\(\Leftrightarrow10x^2-19x-33=0\)

\(\Delta=\left(-19\right)^2-4.10.\left(-33\right)=1320\)

\(x_1=3;x_2=\dfrac{-11}{10}\)

Tick cho mk nha

c) \(\left(3x-5\right)\left(7-5x\right)-\left(5x+2\right)\left(2-3x\right)=4\)

\(\Leftrightarrow21x-15x^2-35+25x-4x+15x^2-4=4\)

\(\Leftrightarrow42x-39=4\)

\(\Leftrightarrow42x=4+39\)

\(\Leftrightarrow42x=43\)

\(\Rightarrow x=\dfrac{43}{42}\)

Tick cho mk nha