10.√a² + 10ab + 25b² при а=7ив= 82

10. $$\sqrt{a^2 + 10ab + 25b^2} = \sqrt{(a+5b)^2} = |a+5b|$$

При $$a = 7\frac{1}{11} = \frac{78}{11}$$ и $$b = \frac{3}{11}$$

$$|a+5b| = |\frac{78}{11} + 5 \cdot \frac{3}{11}| = |\frac{78}{11} + \frac{15}{11}| = |\frac{93}{11}| = \frac{93}{11} = 8\frac{5}{11}$$

Ответ: 8\frac{5}{11}