Răspuns:
Explicație pas cu pas:
[tex]\bf \dfrac{x}{y} = \dfrac{a}{b} \implies b\cdot x = a\cdot y\implies \underline{a\cdot y =b\cdot x }[/tex]
[tex]\bf b\cdot x = 20[/tex]
[tex]\bf a\cdot y =b\cdot x ~~~\bigg|\cdot5\implies 5a\cdot y =5b\cdot x[/tex]
[tex]\bf 5ay =5\cdot 20\implies \red{\underline{5ay = 100\neq 25}}~~Fals[/tex]
