Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(a.=\dfrac{2019}{2020}\times\left(\dfrac{4}{11}+\dfrac{5}{11}+\dfrac{2}{11}\right)\\ =\dfrac{2019}{2020}\times1=\dfrac{2019}{2020}\\ b.=\dfrac{25}{27}\times\left(\dfrac{17}{14}-\dfrac{1}{14}-\dfrac{2}{14}\right)\\ =\dfrac{25}{27}\times1=\dfrac{25}{27}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
a) \(\dfrac{7}{9}\times\dfrac{13}{25}\times\dfrac{9}{7}=\left(\dfrac{7}{9}\times\dfrac{9}{7}\right)\times\dfrac{13}{25}=1\times\dfrac{13}{25}=\dfrac{13}{25}\)
b) \(\dfrac{5}{9}\times\dfrac{21}{25}+\dfrac{21}{25}\times\dfrac{4}{9}\)
\(=\dfrac{21}{25}\times\left(\dfrac{5}{9}+\dfrac{4}{9}\right)\)
\(=\dfrac{21}{25}\times1=\dfrac{21}{25}\)
c) \(\dfrac{19}{5}\times\dfrac{11}{16}-\dfrac{9}{5}\times\dfrac{11}{16}\)
\(=\dfrac{11}{16}\times\left(\dfrac{19}{5}-\dfrac{9}{5}\right)\)
\(=\dfrac{11}{16}\times2=\dfrac{22}{16}=\dfrac{11}{8}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(11\times\left(x-6\right)=4\times x+11\)
\(\Rightarrow11\times x-66=4\times x+11\)
\(\Rightarrow11\times x-4\times x=66+11\)
\(\Rightarrow77\times x=77\)
\(\Rightarrow x=1\)
b) \(\left(2\times x-10\right)\times\left(25-25\times x\right)=0\)
\(\Rightarrow\orbr{\begin{cases}2\times x-10=0\\25-25\times x=0\end{cases}\Rightarrow\orbr{\begin{cases}x=5\\x=1\end{cases}}}\)
a)11x(X-6)=4xX+11
11xX-11x6=4xX+11
11xX-4xX=11x6+11
(11-4)xX=66+11
7xX=77
x=77:7
x=11
b)(2xX-10)x(25-25xX)=0
=>2xX-10=0=>2xX=10 =>x=10:2=5
hoặc 25-25xX=0=>25xX=25=>x=25:25=1
Vậy x=1 hoặc x=5
Tích ch0 mình nha
Cảm ơn bạn nhìu
![](https://rs.olm.vn/images/avt/0.png?1311)
9 - 25 = ( - 7 - x ) - ( 25 - 7 )
9 - 25 = - 7 - x - 25 + 7
9 - 25 = - x - 25
- 14 = - x - 25
=> x thuộc rỗng
11 + ( 15 - 11 ) = - 4 . x - ( 25 - 10 )
11 + 15 - 11 = - 4 . x - 25 + 10
15 = - 4 . x - 15
=> = - 4 . x
17 - { - x - ( - x ) } = - 1
17 + x + x = - 1
17 + 2x = - 1
2x = - 1 - 17
2x = - 18
x = - 18 : 2
x = - 9
=> - x = 9
x + { ( x + 3 ) - [ ( x + 3 ) - ( - x - 2 )]} = x
x + { x + 3 - [ x + 3 + x + 2 ]} = x
x + x + 3 - x - 3 - x - 2 = x
x - x - 2 = 2
x - 2 = 2 - x
=> x = 0
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
2x-(25-4)=11-(15+11)
2x-21=11-26
2x-21=11+(-26)
2x-21=-15
2x=(-15)+21
2x=6
x=6:2
x=3
Chúc bạn hok tốt, bạn nhớ k cho mik nha!!!!!!!
![](https://rs.olm.vn/images/avt/0.png?1311)
Bài 2.Tínhnhẩm:
51 x 11 = 561 | 59 x 11 = 649 |
91 x 11 = 1001 | 45 x 11 =495 |
88 x 11 = 968 | 89 x 11 =979 |
99 x 11 = 1089 | 94 x 11 = 1034 |