B1. In rectangle $A B C D$, the base measures $20 \mathrm{~cm}$. Each vertex is $12 \mathrm{~cm}$ away from the diagonal it does not lie on. Calculate the area of rectangle $A B C D$.
B1. Since triangle $A B E$ is a right triangle, $|A E|=\sqrt{|A B|^{2}-|B E|^{2}}=16 \mathrm{~cm}$. Furthermore, $|A E|$ : $|A B|=|B E|:|B C|$, from which it follows that $|B C|=15 \mathrm{~cm}$ and $S=a b=|A B| \cdot|B C|=300 \mathrm{~cm}^{2}$.

![](https://cdn.mathpix.com/cropped/2024_06_07_c1f0ff7099009a973f5fg-12.jpg?height=248&width=308&top_left_y=453&top_left_x=948)