$
\text{Gegeben:}\\\text{Fläche des Dreiecks} \qquad A \qquad [m^{2}] \\
\text{Kathete} \qquad a \qquad [m] \\
\\ \text{Gesucht:} \\\text{Ankathete zu } \alpha \qquad b \qquad [m] \\
\\ b = \frac{A \cdot 2}{ a}\\ \textbf{Gegeben:} \\ A_{d}=\frac{1}{2}m^{2} \qquad a=4m \qquad \\ \\ \textbf{Rechnung:} \\
b = \frac{A \cdot 2}{ a} \\
A=\frac{1}{2}m^{2}\\
a=4m\\
b = \frac{\frac{1}{2}m^{2} \cdot 2}{ 4m}\\\\b=\frac{1}{4}m
\\\\\\ \small \begin{array}{|l|} \hline A=\\ \hline \frac{1}{2} m^2 \\ \hline 50 dm^2 \\ \hline 5\cdot 10^{3} cm^2 \\ \hline 5\cdot 10^{5} mm^2 \\ \hline 0,005 a \\ \hline 5\cdot 10^{-5} ha \\ \hline \end{array} \small \begin{array}{|l|} \hline a=\\ \hline 4 m \\ \hline 40 dm \\ \hline 400 cm \\ \hline 4\cdot 10^{3} mm \\ \hline 4\cdot 10^{6} \mu m \\ \hline \end{array} \small \begin{array}{|l|} \hline b=\\ \hline \frac{1}{4} m \\ \hline 2\frac{1}{2} dm \\ \hline 25 cm \\ \hline 250 mm \\ \hline 2,5\cdot 10^{5} \mu m \\ \hline \end{array}$