Question

The diagonal of a square is 14 cm. Find its area.

Answer 1

`let \: the \: length \: of \: one \: side \: be \: l \\ {l}^(2) = {14}^(2) - {l}^(2) \\ 2 {l}^(2) = {14}^(2) \\ l√(2) = 14 \\ l = (14)/( √(2) ) \: cm \\ area = \: l * l \\ = ( { (14)/( √(2) )) }^(2) \\ = 98 \: {cm}^(2)`