Tìm m để pt sau có nghiệm: \(\sqrt{x^2-2mx+1}=m-2\)

Tìm m để pt sau có nghiệm:\(\sqrt{\left(1+2x\right)\left(3-x\right)}=2x^2-5x+3+m\)

Giải pt:

1. |x-2|+|x+2|=|2x|
2. |x-2|+|3x-9|=|x+1|
3. \(\left|x^2-4x+2\right|=2x^2-8x+3\)

4. \(\left|x-2016\right|^4+\left|x-2017\right|^5=1\)

Giải pt: \(\sqrt{x-2}+x^2-3x-1=0\)

OPPOSITE.

The government should provide electricity in rural and remote areas.

A.urban. B.mountainous. C.countryside. D.far away.

1. Volunteering makes a significant contribution to the economy all around the world.

A. A contribution from volunteering to the economy has been significantly made.

B. The economy all around the world benefits significantly from volunteering.

C. Volunteers around the world have made significant contribution to the economy.

D. Volunteering has significantly contributed to the world economy in all sectors.

2. Nine volunteers were recruited to take part in the study.

A. The study attracted nine volunteers to take part in.

B. They recruited nine volunteers to take part in the study.

C. All the nine recruited volunteers took part in the study.

D. The recruitment of nine volunteers helped the study a lot.

Clarissa Barton, called Clara, was born in 1821 in Oxford, Massachusetts. At a time when relatively few women worked outside the home, Barton built a career helping others. One of her greatest accomplishments was founding the American Red Cross. This organization helps victims of war and disasters.

Clara Barton taught school for many years. In 1854, she moved to Washington, D.C, and took a job in the government patent office. She was probably the first woman to hold a government job!

When the Civil War began in 1861, Barton volunteered. She gathered supplies to help feed and care for wounded soldiers. She also served as a nurse. Barton possessed excellent organizing skills and knew how to get things done. After the Civil War ended in 1865, Barton took on the job of locating soldiers who were missing. She ran an office that tracked down information on nearly 22,000 men and contacted their families.

Barton took her organizational skills to Europe in 1869. She worked with the International Red Cross to set up hospitals during the Franco-Prussian War (1870-1871) between France and Germany. Barton returned to the United States in 1873.

The Red Cross was founded in Switzerland in the 1860s to care for wounded soldiers during wartime. Nations agreed to follow its policies on the treatment of wounded soldiers by signing a treaty. Barton spent years pushing the United States Congress to approve the International Red Cross treaty. In 1881, she finally won support for creating the American Red Cross. Barton served as president of the organization until 1904.

In 1884, Barton attended an International Red Cross conference in Switzerland. As a result of her efforts, the Red Cross expanded its activities. From helping only victims of war, it began also to help victims of peacetime disasters, such as earthquakes and floods.

Barton's efforts comforted people around the world. Red Cross aid helped people in need during epidemics (outbreaks of disea), floods, famines, and war. Barton became famous for her work.

Clara Barton died in Maryland at the age of 91. She had spent her life helping others.

1. Which of the following could be the best title for the passage?

A. Clarissa Barton. B.the American Red Cross.
C. The Red Cross. D.wounded soldiers.

2. What did Clara Barton NOT do when she was alive according to the passage?

A.founding the American Red Cross.
B.chairing Red Cross conferences.

C.holding a government job.

D.caring for wounded soldiers.

3. The phase "tracked down" in the passage almost means...

A.gathered. B.analyzed. C.searched D.stored

4. How long did Clara Barton work for the American Red Cross?

A.7 years B.44 years C.24 years D.4 years.

5. The word "comforted" in the passage almost means...

A.make someone feel less unhappy

B.help someone feed less disappointed

C.help someone realize dreams

D.make someone believe in themselves.

1. ...means "not open to different opinions".

A.Fortunate B.Obvious C.Narrow-minded D.Dedicated

2.To... is to give something, especially money, to people who need it.

A.donate B.attach C.volunteer D.dedicate

3.I will introduce you... my team leader.

A.for B.to C.with D.on

4.You can... experience in many aspects of life.

A.make B.get C.gain D.do

5.If we... the roads in this area, the economy can develop.

A.stretch B.increase C.widen D.restrict