\(\text{Đề bài}:\frac{5}{2}dm^2=?cm^2\)

\(\text{Trả lời}\)

\(\frac{5}{2}dm^2=250cm^2\)

5/2 dm2=250 cm2 nha

HT

k cho mình nha

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no no no

ko lằm thì đừng nhắn

x-53=456

     x=456 +53

     x=509 

mong bạn k

x=509 nha

HT

k cho mình nha

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My name is Long and I’m a Vietnamese. I am twenty-four years old. I live in Ho Chi Minh city in the south of Vietnam.

I have a big family with six people. I have two sisters and a brother. My sisters are older and my brother is younger than me. My father is a teacher at a secondary school. He has worked for 35 years in the field and he is my biggest role model in life. My mother is a housewife. She is nice and she is really good at cooking. I love my family so much.
I’m a generous and easy-going person but when it comes to work I’m a competitive perfectionist. I’m also an optimis and outgoing person so I have many friends and other social relationships. I enjoy reading, writing and doing math. I decided to become a Civil Engineer because I have always been fascinated by bridges, buildings, and skyscrapers. A degree in Civil Engineering enables me to achieve my goals and also gives me an opportunity to make a difference in the community.

Five years from now, I want to become a project manager of a construction project. As a project manager, my primary goals are managing people, set budgets, and making decisions of all kinds. I also want to speak English fluently so I can work with people from different countries.

1/5 số gạo tẻ đã bán là:

158 + 38 = 196 (kg)

Số gạo tẻ đã bán là:

196 : 1/5 = 980 (kg)

980 kg nha

HT

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A) 1 tờ 200 000 đồng; 1 tờ 100 000 đồng; 1 tờ 50 000 đồng.

B) 1 tờ 200 000 đồng; 1 tờ 100 000 đồng; 1 tờ 50 000 đồng.

_HT_

Can't you do better than that ?

=> Is that the best you can do ?

2/5 dm2=40 cm2 nha

HT

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Chiều rộng bằng số phần chiều dài là: 

\(1\div\left(5-1\right)=\frac{1}{4}\)(chiều dài) 

Nếu chiều rộng là \(1\)phần thì chiều dài là \(4\)phần.

Tổng số phần bằng nhau là: 

\(1+4=5\)(phần) 

Chiều rộng là: 

\(75\div5\times1=15\left(m\right)\)

Chiều dài là: 

\(75-15=60\left(m\right)\)

Answer:

a) \(\left(x-1\right)^2=\left(x-1\right)^2\)

\(\Rightarrow x\inℝ\)

Khẳng định này đúng cho bất kì giá trị nào của x bởi vì cả hai vế đều như nhau.

b) \(5x-\left|9-7x\right|=3\)

\(\Rightarrow\left|9-7x\right|=5x-3\)

\(\Rightarrow\orbr{\begin{cases}9-7x=5x-3\\9-7x=-\left(5x-3\right)\end{cases}}\Rightarrow\orbr{\begin{cases}9+3=5x+7x\\9-3=\left(-5x\right)+7x\end{cases}}\Rightarrow\orbr{\begin{cases}12=12x\\6=2x\end{cases}}\Rightarrow\orbr{\begin{cases}x=1\\x=3\end{cases}}\)

c) \(\left|x+1\right|+\left|x+2\right|+\left|x+3\right|=4x\)

Có \(\hept{\begin{cases}\left|x+1\right|\ge0\\\left|x+2\right|\ge0\\\left|x+3\right|\ge0\end{cases}}\Rightarrow\left|x+1\right|+\left|x+2\right|+\left|x+3\right|\ge0\Rightarrow4x\ge0\)

Mà 4 > 0 \(\Rightarrow x>0\)

\(\Rightarrow x+1+x+2+x+3=4x\)

\(\Rightarrow\left(x+x+x\right)+\left(1+2+3\right)=4x\)

\(\Rightarrow3x+6=4x\)

\(\Rightarrow4x-3x=6\)

\(\Rightarrow x=6\)