If ` a+b+c=5`,`a^2+b^2+c^2=6` then find `ab+bc+ca=`

If a + b- c = 4 and a^(2) + b^(2) + c^(2)= 38 , find ab- bc - ca

If a + b + c= 12 and a^(2) + b^(2) + c^(2) = 50 , find ab + bc + ca

If a+b+ c =9 and a^(2) + b^(2) + c^(2) = 29 , find ab + bc + ca .

If a-b-c= 3 and a^(2) + b^(2) + c^(2) = 77 , find: ab- bc+ ca

If a+b+c =11 and a^(2) + b^(2) + c^(2) =81 , find : ab + bc + ca .

If a^(2) + b^(2) + c^(2) = 35 and ab+ bc + ca= 23 , find a + b+ c

If a^(2) + b^(2) + c^(2) = 50 and ab +bc + ca= 47 , find a + b+ c

Find : a + b+ c , if a^(2) + b^(2) + c^(2) = 83 and ab + bc + ca = 71 .

If a+b+c = 10 and a^(2) + b^(2) + c^(2) = 38 , find : ab + bc + ca

If a,b,c are sides an acute angle triangle satisfying a^(2)+b^(2)+c^(2)=6 then (ab+bc+ca) can be equal to