Mình giải theo kiểu lớp 6 nhá !

=\(33.\left(\frac{34}{15}+\frac{34}{35}+\frac{34}{63}+\frac{34}{99}\right)\)

=\(33.\left[34.\left(\frac{1}{15}+\frac{1}{35}+\frac{1}{63}+\frac{1}{99}\right)\right]\)

=\(33.\left[34.\left(\frac{1}{3.5}+\frac{1}{5.7}+\frac{1}{7.9}+\frac{1}{9.11}\right)\right]\)

=\(33.\left[34.\left(\frac{2}{3.5}+\frac{2}{5.7}+\frac{2}{7.9}+\frac{2}{9.11}\right).\frac{1}{2}\right]\)

=\(33.\left[34\left(\frac{1}{3}-\frac{1}{5}+\frac{1}{5}-\frac{1}{7}+\frac{1}{7}-\frac{1}{9}+\frac{1}{9}-\frac{1}{11}\right).\frac{1}{2}\right]\)

=\(33.\left[34.\left(\frac{1}{3}-\frac{1}{11}\right).\frac{1}{2}\right]\)

=\(33.\left(34.\frac{8}{33}.\frac{1}{2}\right)\)

=\(33.\frac{136}{33}\)

=\(\frac{33.136}{33}\)(*)

=\(136\)

(Bạn có thể bỏ bước có dấu *)

\(7\cdot x+x:\frac{1}{9}+x=3434\)

\(7\cdot x+x\cdot9+x=3434\)

\(\left(7+9+1\right)x=3434\)

\(17\cdot x=3434\)

\(x=3434:17\)

\(x=202\)

\(7\times x+x:\frac{1}{9}+x=3434\)

\(7\times x+x\times9+x=3434\)

\(\left(7+9\right)\times x+x=3434\)

\(16\times x+x=3434\)

\(17\times x=3434\)

\(x=3434:17\)

\(\Rightarrow x=202\)

\(7\cdot x+x\cdot9+x=3434\)

\(x\cdot\left(7+9+1\right)=3434\)

\(x\cdot17=3434\)

\(x=3434:17=202\)

 (  3434/3535 + 3434/6363 + 3434/9999 ) × 55

= (  34/35 + 34/63 + 34/99 ) × 55

= 34 × ( 1/35 + 1/63 + 1/99 ) × 55

=  34 × 3/55 × 55

= 102/55 × 55

= 102

Mình ko chắc lắm đâu nhá

b) \(\left|5x-3\right|-x=7\)

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

\(\Rightarrow\orbr{\begin{cases}5x-3=7+x\\5x-3=-\left(7+x\right)\end{cases}\Rightarrow\orbr{\begin{cases}5x-3=7+x\\5x-3=-7-x\end{cases}\Rightarrow}\orbr{\begin{cases}5x-x=7+3\\5x+x=-7+3\end{cases}}}\)

\(\Rightarrow\orbr{\begin{cases}4x=10\\6x=-4\end{cases}\Rightarrow\orbr{\begin{cases}x=\frac{5}{2}\\x=-\frac{2}{3}\end{cases}}}\)

Vậy .................... 

Bạn ơi !!! ý A tham khảo tại link này nè :

https://h.vn/hoi-dap/question/394208.html

~ Học tốt ~

Bạn ơi ko vào được

Ta có: \(\frac{1717}{8585}=\frac{17.101}{85.101}=\frac{17}{85}=\frac{1}{5}=\frac{13}{65}\)

\(\frac{1313}{5151}=\frac{13.101}{51.101}=\frac{13}{51}\)

Vì \(\frac{13}{65}< \frac{13}{51}\) nên \(\frac{1717}{8585}< \frac{1313}{5151}\)

Ta có :

\(\frac{1717}{8585}=\frac{1717:1717}{8585:1717}=\frac{1}{5}\);

\(\frac{1313}{5151}=\frac{1313:101}{5151:101}=\frac{13}{51}\)

Vì : 1/5 = 0,2 và 13/51 = 0,25...

=> 1717/8585 < 1313/5151 

\(\frac{x+1}{9}+\frac{x+4}{6}+\frac{x+5}{5}=\frac{x+2}{8}+\frac{x+3}{7}+\frac{x+6}{4}\)

\(\Rightarrow\frac{x+1}{9}+\frac{x+4}{6}+\frac{x+5}{5}+3=\frac{x+2}{8}+\frac{x+3}{7}+\frac{x+6}{4}+3\)

\(\Rightarrow\left(\frac{x+1}{9}+1\right)+\left(\frac{x+4}{6}+1\right)+\left(\frac{x+5}{5}+1\right)=\left(\frac{x+2}{8}+1\right)\)\(+\left(\frac{x+3}{7}+1\right)+\left(\frac{x+6}{4}\right)\)

\(\Rightarrow\frac{x+10}{9}+\frac{x+10}{6}+\frac{x+10}{5}=\frac{x+10}{8}+\frac{x+10}{7}+\frac{x+10}{4}\)

\(\Rightarrow\left(x+10\right)\left(\frac{1}{9}+\frac{1}{6}+\frac{1}{5}\right)=\left(x+10\right)\left(\frac{1}{8}+\frac{1}{7}+\frac{1}{4}\right)\)

\(\Rightarrow\left(x+10\right)\frac{43}{90}=\left(x+10\right)\frac{29}{56}\)

\(\Rightarrow x+10=0\)

\(\Rightarrow x=-10\)

cộng 3 vào cả hai vế nên phương trình vẫn bằng nhau

Ta có \(\frac{x+1}{9}+1+\frac{x+4}{6}+1+\frac{x+5}{5}+1=\frac{x+2}{8}+1+\frac{x+3}{7}+1+\frac{x+6}{4}+1\)

\(\Leftrightarrow\frac{x+10}{9}+\frac{x+10}{6}+\frac{x+10}{5}=\frac{x+10}{8}+\frac{x+10}{7}+\frac{x+10}{4}\)

\(\Leftrightarrow\frac{x+10}{9}+\frac{x+10}{6}+\frac{x+10}{5}-\frac{x+10}{8}-\frac{x+10}{7}-\frac{x+10}{4}=0\)

\(\Leftrightarrow\left(x+10\right)\left(\frac{1}{9}+\frac{1}{6}+\frac{1}{5}-\frac{1}{8}-\frac{1}{7}-\frac{1}{6}\right)=0\)

mà \(\frac{1}{9}+\frac{1}{6}+\frac{1}{5}-\frac{1}{8}-\frac{1}{7}-\frac{1}{6}\ne0\)

\(\Rightarrow x+10=0\)

\(\Leftrightarrow x=-10\)

tự làm để nc trí óc dễ

           3 + \(\frac{3}{20}\)+   \(\frac{3}{13}\) + \(\frac{3}{2013}\)

X x                                                                =  \(\frac{5}{3}\)

            5 + \(\frac{5}{20}\) +  \(\frac{5}{13}\) + \(\frac{5}{2013}\)

          3 x ( 1 +  \(\frac{1}{20}\) + \(\frac{1}{13}\) + \(\frac{1}{2013}\) )

X  x                                                                        =  \(\frac{5}{3}\)

          5 x ( 1 + \(\frac{1}{20}\) +\(\frac{1}{13}\) +  \(\frac{1}{2013}\) ) 

X  x  \(\frac{3}{5}\) =   \(\frac{5}{3}\) => X =  \(\frac{25}{9}\) vậy X = \(\frac{25}{9}\)

Ta có  : \(X.\frac{3+\frac{3}{20}+\frac{3}{13}+\frac{3}{2013}}{5+\frac{5}{20}+\frac{5}{13}+\frac{5}{2013}}=\frac{5}{3}\)

\(\Leftrightarrow X.\frac{3\left(1+\frac{1}{20}+\frac{1}{13}+\frac{1}{2013}\right)}{5\left(1+\frac{1}{20}+\frac{1}{13}+\frac{1}{2013}\right)}=\frac{5}{3}\)

\(\Leftrightarrow X.\frac{3}{5}=\frac{5}{3}\Rightarrow X=\frac{5}{3}:\frac{3}{5}=\frac{5}{3}.\frac{5}{3}=\frac{25}{9}\)

Ta co 

\(\frac{x+2}{327}+1+\frac{x+3}{326}+1+\frac{x+4}{325}+1+\frac{x+5}{324}+1+\frac{x+349}{5}-4\)=0

\(\Rightarrow\frac{x+329}{327}+\frac{x+329}{326}+\frac{x+329}{325}+\frac{x+329}{324}+\frac{x+329}{5}=0\)

\(\Rightarrow\left(x+329\right).\left(\frac{1}{327}+\frac{1}{326}+\frac{1}{325}+\frac{1}{324}+\frac{1}{5}\right)=0\)

Vì \(\frac{1}{327}+\frac{1}{326}+\frac{1}{325}+\frac{1}{324}+\frac{1}{5}>0\)

\(\Rightarrow x+329=0\Rightarrow x=-329\)

Vay \(x=-329\)

ok bn. Thanks bạn nha ! <3

còn -4 đâu?

x=-100

\(\frac{x+5}{95}+\frac{x+6}{94}+\frac{x+7}{93}+\frac{x+8}{92}+\frac{x+9}{91}=-5\)

\(\left(\frac{x+5}{95}+1\right)+\left(\frac{x+6}{94}+1\right)+\left(\frac{x+7}{93}+1\right)+\left(\frac{x+8}{92}+1\right)+\left(\frac{x+9}{91}+1\right)=-5+5=0\)

x=100

k hộ với