5. \(\alpha : \gamma = 3 : 7\), \(\alpha = ?\), \(\gamma = ?\)

Поскольку \(\alpha\) и \(\gamma\) - смежные углы, то \(\alpha + \gamma = 180^{\circ}\). Пусть \(\alpha = 3x\), а \(\gamma = 7x\). Тогда \(3x + 7x = 180^{\circ}\), \(10x = 180^{\circ}\), \(x = 18^{\circ}\). Следовательно, \(\alpha = 3 \cdot 18^{\circ} = 54^{\circ}\), \(\gamma = 7 \cdot 18^{\circ} = 126^{\circ}\). Ответ: \(\alpha = 54^{\circ}\), \(\gamma = 126^{\circ}\)