Question

hiệu x-y biết x+3/y+5=x+5/y+7

Answer 1

Ta suy ra:

x+3/y+5 = x+5/y+7  = (x+3-x-5)/(y+5-y-7) = -2/-2 =1

x+3 /y+5 =1 => x+3 =y+5

                   => x-y = 5-3 =2

Vay x-y =2

Answer 2

Ap dung tinh chat day ti so bang nhau : 

x+3/y+5=x+5/y+7=(x+5)-(x+3)/(y+7)-(y+5)=x+5-x-3/y+7-y-5=2/2=1

Suy ra : x+3/y+5=1=>x+3=y/5

=>x-y=5-3=2

Vay x-y=2

**** nhe