Bài 2: Chọn C

Bài 4: 

a: \(\widehat{C}=180^0-80^0-50^0=50^0\)

Xét ΔABC có \(\widehat{A}=\widehat{C}< \widehat{B}\)

nên BC=AB<AC

b: Xét ΔABC có AB<BC<AC

nên \(\widehat{C}< \widehat{A}< \widehat{B}\)

Bài 2.8
Cửa hàng lãi:\(\left(1000000:800000\right)-100\%=25\%\left(giavon\right)\)
Bài 2.9
Số tiền phải bán để lãi 25% giá vốn:\(740000+\left(740000\times25\%\right)==925000\left(đồng\right)\)

1 If we continue polluting the air, the environment will be affected seriously

2 If we don't stop damaging birds' homes, there will be fewer birds left

3 If we continue polluting the water, there will be more disease in people and animals

4 If we keep polluting the land, the soil will not be safe enough for us to grow food in

5 If we use public transportation when we need, there will be less air pollution

12 Daniel signs up for a clean-up campaign so that he can join in it

13 People in my neighborhood clean the park up so that their children will have a nice place to play

14 Almost all the students in my school plant trees so that they can have much fresher air

Bài 7:

a: a>b

nên -2a<-2b

=>-2a-6<-2b-6<-2b

b: a>b

nên 3a>3b

=>3a-9>3b-9

=>3(a-3)>3(b-3)

Overcrowding is a pressing issue that affects many communities around the world. It refers to a situation where the number of people living in a particular area exceeds its capacity. This can occur due to rapid population growth, urbanization, and migration, coupled with insufficient housing infrastructure. The effects of overcrowding are far-reaching and detrimental. Firstly, it poses significant health risks as it increases the likelihood of the spread of diseases. Additionally, overcrowded areas often experience higher crime rates, as the lack of space and resources can lead to heightened tensions. Moreover, overcrowding puts a strain on public services and resources, such as schools, hospitals, and transportation systems. To address this issue, it is crucial to implement effective urban planning and development strategies, along with initiatives to provide affordable housing. Furthermore, improving transportation systems can help distribute the population more evenly. Lastly, population control measures should be considered to manage the growth rate. In conclusion, overcrowding is a complex problem that requires collective efforts from individuals and governments. By taking proactive steps, we can create healthier and more sustainable communities for future generations.

$HaNa♬☘$

\(P=\dfrac{x^3+8y^3}{4^3+4^3}=\dfrac{\left(x+2y\right)^3-3\cdot x\cdot2y\cdot\left(x+2y\right)}{128}\)

\(=\dfrac{\left(-8\right)^3-6\cdot\left(-6\right)\cdot\left(-8\right)}{128}=\dfrac{128-6\cdot48}{128}=-\dfrac{5}{4}\)