Question

if a square + b square + c square equals to 220 and a b + BC + ca = to 4 then find the value of a + b +c

Answer 1

(a+b+c)²=a²+b²+c²+2(ab+bc+ca)
(a+b+c)²=220+2(4)
(a+b+c)²=228
a+b+c=√228