Question

What is the area of a square whose diagonal measures 5cm?

Answer 1

Area of a square in terms of diagonal is given by

Given d = 5 cm
Area = 1/2 ( d² )
where 'd' is diagonal

Area  = 1/2 ( 5² )
         = 1/2 (25 )
         = 12.5 cm²

Answer 2

area = 1/2 d^2

so answer is 1/2 * 25 = 12.5cm²