HN // KI
Áp dụng định lý ta lét:
\(\dfrac{HN}{KI}=\dfrac{HQ}{KO}\)
\(\Leftrightarrow\dfrac{3}{6}=\dfrac{x}{3,5}\)
\(\Leftrightarrow6x=10,5\Leftrightarrow x=\dfrac{7}{4}\)
Theo hệ quả Ta lét \(\dfrac{NQ}{NK}=\dfrac{HN}{KT}\Rightarrow\dfrac{x}{x+3,5}=\dfrac{3}{6}\Rightarrow x=3,5\)
Theo định lí Ta lét \(\dfrac{HQ}{QI}=\dfrac{NQ}{KQ}\Rightarrow\dfrac{2}{y}=\dfrac{3,5}{3,5}\Rightarrow y=2\)

