по теореме косинусов

[tex]37^2 = 33^2 + 7^2 - 2 \times 33 \times 7 \times \cos( \beta ) \\ [/tex]

[tex] \cos( \beta) = \dfrac{ - 231}{462} = \dfrac{ - 1}{2} [/tex]

[tex] \beta = 120°[/tex]