79,5 % của 100 là :

     100 : 100 x 79,5 = 79,5

          Đáp số : 79,5 .

Số chia 24 dư 17 có dạng là:24k+17

Ta có:24k+17=24k+12+5=12(2k+1)+5 chia 12 dư 5

Vậy số A là:

  85x12+5=1025

     Đáp số:1025

mía thế để tôi làm cho

\(\Leftrightarrow\frac{1}{x}+\frac{1}{\sqrt{^2\left(2-x\right)}}=\frac{-2}{\left(x-2\right)x}\)

\(\Rightarrow\frac{-2}{\left(x-2\right)x}=2\)

\(\Leftrightarrow\frac{1}{x}+\frac{1}{2-x}=2\)

\(\Rightarrow\frac{1}{x}+\frac{1}{2-x}-2=0\)

\(\Leftrightarrow\frac{-2\left(x^2-2x+1\right)}{\left(x-2\right)x}=0\)

áp dụng denta

<=>\(x^2-2x+1=0\)

\(\Rightarrow\left(-2\right)^2-4\left(1.1\right)=0\)

\(\Rightarrow x_{1,2}=\frac{-b+-\sqrt{\Delta}}{2a}=\frac{2+-\sqrt{0}}{2}\)

=> 2 nghiệm của x đều =1

=>x=1

Tìm x, biết:

a)  x − 3 2 + 11 4 = 15 4

b)  17 4 − 5 6 − x = − 7 4

Với giá trị x thỏa mãn 2 x 2  – 7x + 3 = 0, tính giá trị phân thức:

a) x 2 − 2 x + 1 2 x 2 − x − 1 ;             b)  x 3 − 27 x 2 − 2 x − 3 .

Read the following pasage and decide which answer (A, B, C or D) best fits each space from 1 to 5.

With job vacancies available all year round offering high salaries, Vietnam has been ranked the second best place in the world to teach English by TEFL Exchange, a community for teachers of English (1)______ a foreign language.

The site (2)______ that a foreign English teacher can earn between 1,200-2,200 USD a month in Vietnam, where the average annual income in 2016 was just 2,200 USD. They can (3)______ a job any time of year and the best places to do so are the country’s three largest cities: Hanoi, Ho Chi Minh City and Da Nang. Candidates only need to hold a bachelor’s (4)______ and a TEFL (Teaching English as a Foreign Language) certificate.

English is an obligatory subject from sixth grade across Vietnam, but in large cities, many primary schools demand high (5)______. Foreign language centers have been thriving here, with students as young as three years old.

Điền vào ô 1.

A. like

B. similar

C. as

D. for

Thực hiện phép tính:  3 5 + − 2 5