As 8.25448.2544 is not a complete square, let us use long division method for taking square root.
color(white)(xxx)2color(white)(xx).8color(white)(xx)7color(white)(xx)3×x2×.8×7×3
ul2|bar(8).color(white)(.)bar(25)color(white)(.)bar(44)color(white)(.)bar(00)color(white)(.)bar(00)
color(white)(XX)ul(4)color(white)(X)darr
color(red)(4)8|color(white)(X)4color(white)(.)25
color(white)(xxXx)ul(3color(white)(.)84)
color(white)(x)color(red)(56)7|color(white)(X)41color(white)(.)44
color(white)(xxxxxx)ul(39color(white)(.)69)
color(white)(xx)color(red)(574)3|1color(white)(x)75color(white)(.)00
color(white)(xxxxx.x)ul(1color(white)(.)72color(white)(.)29)
color(white)(xxx)color(red)(11486)|color(white)(.)2color(white)(.)71
Hence sqrt8.2544~~2.873