The image you uploaded contains a set of math problems in Russian, specifically focusing on inequalities and their properties. Let's break down each part and translate them step by step.

1. Define whether the number $c$ is positive or negative:

• a) $9,1 < c < 0$
• b) $-5c > 0$

2. Compare the numbers $a$ and $b$, if:

• a) $a > b$
• b) $a - b = -8$
• c) $a - b = 0$

3. Given the expressions $6c(c + 4)$ and $2c(c - 2)$, compare their values when $c = -3$.

4. It is known that $a < b$. Compare:

• a) $-\frac{4}{3}a$ and $-\frac{4}{3}b$
• b) $\frac{6}{7}a$ and $\frac{6}{7}b$
• c) $a - 3,2$ and $b - 3,2$
• d) $5 + a$ and $5 + b$

5. Prove that if $5m - 8n < 3n - 6m$, then $m < n$.

6. Prove that if $m(m + 5) > (m + 3)^2$, then $m < -9$.

Let me know if you'd like to solve any of these problems, or if you want to explore specific steps in more detail.