Đặt \(\frac{a}{b}=\frac{c}{d}=k\)

\(\Rightarrow a=bk;c=dk\)

Ta có:

\(VT=\frac{a+b}{a-b}=\frac{bk+b}{bk-b}=\frac{b\left(k+1\right)}{b\left(k-1\right)}=\frac{k+1}{k-1}\left(1\right)\)

\(VP=\frac{c+d}{c-d}=\frac{dk+d}{dk-d}=\frac{d\left(k+1\right)}{d\left(k-1\right)}=\frac{k+1}{k-1}\left(2\right)\)

Từ (1) và (2) ->đpcm

0,3m=3dm

7,54m=754cm

2,5m=250cm

0,534kg=534g

0,28kg=280g

1,5g=1,5g

150 - (x:5 + 2).3 = 108 

(x:5 + 2).3 = 42 

x:5 + 2 = 126 

x:5 = 124 

x = 620 

100 + 100 = 200