912 x 4 = 3648

 912 x 4 = 3648.

So can tim la:

912x4=3648

Vay so do la:3648

*** k mk nha!

a) x x 4 = 912

      x = 912 : 4

      x = 228

b) x : 3 = 248

      x = 248 x 3

      x = 744

24/54

\(\dfrac{24}{54}\)

24/54

`13-6=7`

`15-7=8`

`12-4=8`

`11-2=9`

`14-5=9`

`17-8=9`

`16-8=8`

`18-9=9`

`12-3=9`

Tính nhẩm.

13 - 6=7                           11 - 2 =9                          16 - 8=8

15 - 7 =8                          14 - 5=9                           18 - 9=9

12 - 4 =8                          17 - 8 =9                           12 - 3=9

13-6=7   11-2=9      16-8=8

15-7=8    14-5=9      18-9=9

12-4=8     17-8=9      12-3=9

46+(88-4.x):4=65

(88-4.x):4=65-46

(88-4.x):4=19

88-4.x=19.4

88-4.x=76

4.x=88-76

4.x=12

x=12:4

x=3

912-(476-16.x):7=69

(476-16.x):7=912-69

(476-16.x):7=843

476-16.x=843.7

476-16.x=5901

16.x=476-5901

16.x=(-5425)

x=(-5425):16

x=(-339,0625)

li-ke cho mình nha mình đang cần li-ke

46 + ( 88 - 4x ) : 4 = 65

( 88 - 4x ) : 4= 65- 46

( 88 - 4x ) = 19

( 88 - 4x ) = 19x 4

88-4x = 76

4x = 88- 76

4x = 8

x = 8 : 4

x = 2

`3x+20=0`

`=>3x=0-20`

`=>3x=-20`

`=>x=-20/3`

`---`

`2(-4x+9)=0`

`=>-4x+9=0`

`=>-4x=-9`

`=>x=9/4`

`---`

`2x(x-45)=0`

\(\Rightarrow\left[{}\begin{matrix}2x=0\\x-45=0\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=0\\x=45\end{matrix}\right.\)

`---`

`-5x(2x+47)=0`

\(\Rightarrow\left[{}\begin{matrix}-5x=0\\2x+47=0\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=0\\x=-\dfrac{47}{2}\end{matrix}\right.\)

`----`

`x^2 -912=0`

`=>x^2=912`

`=>x∈∅`

1)

`3x+20=0`

`<=>3x=-20`

`<=>x=-20/3`

2)

`2(-4x+9)=0`

<=>-4x+9=0`

`<=>-4x=-9`

`<=>x=9/4`

3)

`2x(x-45)=0`

\(< =>\left[{}\begin{matrix}2x=0\\x-45=0\end{matrix}\right.\\ < =>\left[{}\begin{matrix}x=0\\x=45\end{matrix}\right.\)

4)

`-x(2x+47)=0`

\(< =>\left[{}\begin{matrix}-x=0\\2x+47=0\end{matrix}\right.\\ < =>\left[{}\begin{matrix}x=0\\x=-\dfrac{47}{2}\end{matrix}\right.\)

5)

`x^2 -912=0`

`<=>x^2=912`

câu 5 xem lại nhé

tìm nghiệm của đa thức ạ

9 1 2   :   5 5 8 = 19 2   :   45 8 = 19 2 × 8 45 = 76 45

Đáp án cần chọn là D