[tex]6)~~~\ \textless \ C = \ \textless \ C (unghi comun) \\
\ \textless \ A = \ \textless \ BDC \\
Suntem ~in~cazul~UU~de~asemanare. \\
=\ \textgreater \ \Delta CDB \sim \Delta CAF \\
\text{Atentie la ordinea in care scrii literele} \\ CBD \sim \Delta CAF
Adica~~~ CDB \sim \Delta CAF~~~dar ~~~ CBD \nsim \Delta CAF ~~(nu~e)[/tex]
[tex]7) \displaystyle \\
AB = 5\;cm \\ \\
AC = \frac{2}{9}\times 5 = \frac{10}{9}\;cm = 1,(1) \;cm \\ \\
CD = \frac{5}{9}\times 5 = \frac{25}{9}\;cm =2,(7)\;cm\\ \\
BD = \frac{2}{9}\times 5 = \frac{10}{9}\;cm = 1,(1) \;cm [/tex]
[tex]2)~~~\text{Suma unghiurilor intr-un patrulater }= 360^o\\
x = 360 - 90 - 90 - 142 = 180 - 142 = 38^o[/tex]
