\((a+b)^2= a^2 + 2ab +b ²\)
\((a-b)^2= a^2 - 2ab +b ²\)
\(A = {1\over 2} \cdot g \cdot h\)
\(A = {a+c \over 2} \cdot h\)
\(h = {2 \cdot A \over a+c}\)
\(a+c= {2\cdot A \over h}\)
\(a = {2\cdot A \over h}-c \quad\) und \(\quad c = {2\cdot A \over h}-a\)