Question

Daca x/y=7/3, calculati valoarea raportului x^2-xy/x^2+xy.

Answer 1

x/y=7/3=k⇒ x=7k si y=3k
x²-xy/x²+xy = x(x-y)/x(x+y)= x-y/x+y= 7k-3k/7k+3k= 4k/10k=4/10=2/5=0,4

Answer 2

 [tex]\frac{x}{y}=\frac{7}{3}\\ conform\;proprietatiilor\;proportiilor\;derivate\,cu\;termeni \;schimbati\\ avem:\;\;\frac{x-y}{x+y}=\frac{7-3}{7+3}\;!!!\\ Valoarea\;raportului\; va \;fi:\;...=\frac{x(x-y)}{x(x+y)}=\frac{7-3}{7+3}=0,4=\frac{4^{(2}}{10}=2/5[/tex]