21/49=3/7

36/98=18/49

18/34=9/17

k cho mik nha!

ko có ps nào =34

hoặc sai đề

Phân số bằng 34 là;...........

^{_{\(\dfrac{5}{7}=\dfrac{15}{21};\dfrac{6}{8}=\dfrac{3}{4};\dfrac{8}{9}=\dfrac{16}{18};\dfrac{12}{16}=\dfrac{18}{24}\)}}

\(\dfrac{5}{7}=\dfrac{15}{21};\dfrac{6}{8}=\dfrac{18}{24};\dfrac{8}{9}=\dfrac{16}{18};\dfrac{3}{4}=\dfrac{12}{16}\)

5/7=15/21;6/8=3/4;8/9=16/18;12/16=18/24

a: 5/3=10/6=25/15=35/21

b: 5/7=35/49

6/15=12/30

4/5=16/20

c: 6=216/36=324/54=108/18

a)\(\dfrac{5}{3}=\dfrac{10}{6}=\dfrac{25}{15}=\dfrac{35}{21}\)

b)\(\dfrac{5}{7}=\dfrac{35}{49};\dfrac{6}{15}=\dfrac{12}{30};\dfrac{4}{5}=\dfrac{16}{20}\)

c) \(6=\dfrac{216}{36}=\dfrac{324}{54}=\dfrac{108}{18}\)

Bài 2 : a, x = -36/9 = -4

b, đề sai 

c, <=> -2 =< x =< -3 => x = -1 

Bài 1: 

a: 2/8=9/36; 2/9=8/36; 8/2=36/9; 9/2=36/8

b: -2/4=9/-18; -2/9=4/-18; 4/-2=-18/9; 9/-2=-18/4

Bài 2: 

a: =>x/3=-4/3

hay x=-4

Câu b đề sai rồi bạn

\(\dfrac{18}{21}=\dfrac{6}{7}\)=\(\dfrac{12}{14}=\dfrac{36}{42}\)=\(\dfrac{90}{150}=\dfrac{3}{5}\)=\(\dfrac{12}{20}=\dfrac{60}{100}=\dfrac{21}{35}\)

\(\dfrac{18}{21}=\dfrac{12}{14}=\dfrac{6}{7}=\dfrac{36}{42}\)

\(\dfrac{90}{150}=\dfrac{12}{20}=\dfrac{60}{100}=\dfrac{3}{5}=\dfrac{21}{35}\)

a ta co xét ti le xích  1/3=4/12 nhan hai ti so cua ti le thức với  3*12 ta dược 1/3*(3*12)=4/12*(3*12)=>1*12=4*3

Cung de Ma Nho tích cho minh nha con cau b chua lam thong cảm

a, 11\12=33\36 ;  4\5=76\95

b, 7\6=49\42  ;  8\9=184\207

   hok tốt