Question

If ( a+b+c) =9 , ab+bc+ca=53, then find the a²+b²+c²​

Answer 1

Answer:

a^2+b^2+c^2=(a+b+c)^2-2(ab+bc+ca)

=9^2-2.53=81-106= -25

Answer 2

Answer:

we know that (a+b+c)^2=a^2+b^2+c^2+2ab+2bc+2ca

(9)^2=a^2+b^2+c^2+2(ab+bc+ca)

81=a^2+b^2+c^2+2(53)

81=a^2+b^2+c^2+106

a^2+b^2+c^2=(-25)