Find the distance

(-2,8) and (-8,-4)

Distance  =   sqrt [  ( -8 - -2)^2 + ( -4 - 8)^2 ] =

sqrt [ (-6)^2 + (-12)^2 ] =

sqrt [ 36 + 144]  =

sqrt [ 180] =

sqrt [ 36 * 5] =

6*sqrt(5)   = about 13.4 units