Odpowiedź:
[tex]30 + 90 + \beta = 180\\\beta = 180 - 90 - 30\\\beta = 60[/tex]
[tex]sin30 = \frac{\sqrt{12}}{c} \\\frac{1}{2} = \frac{\sqrt{12}}{c}\\2\sqrt{12} = c\\b^2 = (2\sqrt{12})^2 + \sqrt{12}^2\\b^2 = 48 + 12\\b^2 = 60\\b = \sqrt{60} = 2\sqrt{15}[/tex]
