[tex]a=5dm\\b=9dm\\Ob=a+b+2c=30dm\\5dm+9dm+2c=30dm\\14dm+2c=30dm /-14dm\\2c=16dm /:2\\c=8dm\\\\cos\alpha=\frac{2dm}{8dm}=\frac14\\\alpha=75^\circ\\\beta=180^\circ-75^\circ=105^\circ\\\\\text{Miary katow tego trapezu to: }75^\circ, 75^\circ, 105^\circ, 105^\circ[/tex]
