Step-by-step explanation:
well there is a very simple point that you have mistaken tho:
484cm², 25cm²
Areas are defined in square cm but the radius is in cm
so:
[tex] \sqrt{ \frac{484 {cm}^{2} }{25 {cm}^{2} } } = \frac{7.92}{r} = = = > 4.4 = \frac{7.92cm}{x} = = > x = \frac{7.92cm}{4.4} = x = 1.8cm[/tex]
and there you go
