Question 158814
You are asked for the sum of the [squares]
You need to pay more attention to what is given & asked for. 
x + (x + 2)+ (x + 4)= 116 [x^2+(x+2)^2+(x+4)^2=116]
3x + 6 = 116              [x^2+x^2+4x+4+x^2+8x+16=116]
-6 - 6                    [3x^2+12x+20-116=0]
                          [3x^2 +12x-96=0]
3x = 110                  [3(x^2+4x-32)=0] 
3x/3 110/3                3(x+8)(x-4)=0] 
x = 36.6666               [x-4=0]
                          [x=4]
Proof:
4^2+6^2+8^2=116
16+36+64=116
116=116