\[a,\ b,\ c,\ d - углы\ трапеции:\]
\[\angle a = 46{^\circ}.\]
\[1)\ По\ свойству\ равнобокой\ \]
\[трапеции:\]
\[\angle d = \angle a = 46{^\circ};\ \ \ \]
\[\angle b = \angle c.\]
\[2)\ \angle a + \angle b + \angle c + \angle d = 360{^\circ}\]
\[46{^\circ} + \angle b + \angle b + 46{^\circ} = 360{^\circ}\]
\[2\angle b = 268{^\circ}\ \ \ \]
\[\angle b = 134{^\circ}.\]
\[Ответ:\ \ 46{^\circ};\ 134{^\circ};\ 46{^\circ};\ 134{^\circ}.\]