1. The first expression is $3x2^2 = 6H$. 2. Calculate the power term: $2^2 = 4$. 3. Substitute back: $3 \times 4 = 6H$ which simplifies to $12 = 6H$. 4. Solve for $H$ by dividing both sides by 6: $$H = \frac{12}{6} = 2$$. 5. The second expression is $\frac{8}{28} = \frac{3}{8}$. 6. Simplify the left side fraction: $\frac{8}{28} = \frac{2}{7}$. 7. Compare $\frac{2}{7}$ with $\frac{3}{8}$; since cross-multiplying gives $2 \times 8 = 16$ and $3 \times 7 = 21$, they are not equal. 8. The third expression is unclear but might be intended as $(im \ 7 \ xi \ m)$. 9. Without more clarity, this expression cannot be solved or interpreted further.