Answers

The Brainliest Answer!
2015-06-04T10:45:35+05:30
(a+b+c)²=a²+b²+c²+2(ab+bc+ca)
            =250+2×3
             =256
a+b+c=√256
          =16
1 5 1
2015-06-04T10:50:22+05:30
Given- a2+b2+c2 = 250
          ab+bc+ca=3
using identity (a+b+c)^2=a2+b2+b2+2ab+2bc+2ca
(a+b+c)^2= 250+2(3)
               = 256
                a+b+c=  √256
                      =+- 16

(mean 16 is in positive and negative) 


1 5 1
You are the real brainless.
Not brainless it is brainiest.