44. Exemplar Exercise Problems XVIII

1. Diagonals \(AC\) and \(BD\) of a parallelogram \(ABCD\) intersect each other at \(O\). If \(OA = 3 cm\) and \(OD = 2 cm\), determine the lengths of \(AC\) and \(BD\).

 

\(AC=\) \(cm\)

 

\(BD=\) \(cm\)

 

2. In \(△ ABC\), \(AB = 5 cm\), \(BC = 8 cm\) and \(CA = 7 cm\). If \(D\) and \(E\) are respectively the mid-points of \(AB\) and \(BC\), determine the length of \(DE\).

 

\(DE=\)\(cm\)