[tex]1)P_{\boxed{ }} =P_{\boxed{~}} \\
A_{\boxed{}}=64~cm^2 \\
l^2=64 \Longrightarrow l=8~cm \\
P_{\boxed{}}=8*4=32~cm \\
P_{\boxed{~}}=32~cm \\
2(L+l)=32 \\
L+l=16 \\
10+l=16 \Longrightarrow \boxed{l=6~cm} \\ \\
2)ABCD~paralelogram;~AB||DC~si~AD||BC \\
AD=5~cm \\
BD \perp AD; BD=12~cm \\
\triangle ADB:D=90^{\circ} \longrightarrow A= \frac{AD*BD}{2}= \frac{12*5}{2}=30~cm^2 \\
A_{ABCD}=2*30 \\
\boxed{A_{ABCD}=60~cm^2} [/tex]
[tex]3)A_{trapez}= \frac{h*(B+b)}{2} \\
l.m= \frac{B+b}{2}=10~cm \\
h=7~cm \\
A_{trapez}=l.m*h=10*7 \\
\boxed{A_{trapez}=70~cm^2} \\ \\[/tex]
