study / i / a / twice / with / week / partner / a / .

=>  I study with a partner twice a week.

parents / My / in / live / small / in / a / the / village / countryside / in / .

=> My parents live in a small village in the countryside.

always / his / father / up / at /gets / 5.30 / morning / every / .

=> His father always gets up 5.30 every morning.

august / 1st / born / I / 1995 / on /was

=> I was born on August 1st 1995.

he / want / play /soccer / not / doesn't

=> He doesn't want to play soccer.

4) \(\dfrac{423134\times846267-423133}{423133\times846267+423134}\)

\(=\dfrac{\left(423133+1\right)\times846267-423133}{423133\times846267+423134}\)

\(=\dfrac{423133\times846267+\left(1\times846267-423133\right)}{423133\times846267+423134}\)

\(=\dfrac{423133\times846267+423134}{423133\times846267+423134}=1\)

5) \(\dfrac{1978\times1979+1980\times21+1958}{1980\times1979-1978\times1979}\)

\(=\dfrac{1978\times1979+\left(1979+1\right)\times21+1958}{1980\times1979-1978\times1979}\)

\(=\dfrac{1978\times1979+1979\times21+21+1958}{1979\times\left(1980-1978\right)}\)

\(=\dfrac{1979\times\left(1978+21\right)+1979}{1979\times2}\)

\(=\dfrac{1979\times1999+1979}{1979\times2}\)

\(=\dfrac{1979\times\left(1999+1\right)}{1979\times2}=\dfrac{1979\times2000}{1979\times2}=1000\)

7^{x + 3} - 7^{x + 1} = 16464

\(\Leftrightarrow7^x.7^3-7^x.7=16464\)

\(\Leftrightarrow7^x.\left(7^3-7\right)=16464\)

\(\Leftrightarrow7^x.336=16464\)

\(\Leftrightarrow7^x=49\Leftrightarrow7^x=7^2\)\(\Rightarrow x=2\)

Vậy x = 2

Gọi số điểm là n (n \(\in\) N, n \(\ge\) 2)

Áp dụng công thức, ta có: 

 \(\dfrac{n.\left(n-1\right)}{2}=28\Rightarrow n.\left(n-1\right)=28.2=56=7.8\)

Suy ra n = 8

Vậy có 8 điểm cho trước