Sum of the squares of three numbers is 138 and the sum of their products taken two at a time is 131. Find the sum? Choose one:
A) 20  B) 25  C) 27  D) 29  E) 30
(a + b + c)2 = a2 + b2 + c2 + 2(ab +bc + ca) = 138 + 2* 131   a + b + c = √400 = 20   20
<result>A</result>
Sum of the squares of three numbers is 138 and the sum of their products taken two at a time is 131. Find the sum?