Question

if a+b+c=9 ,ab+bc+ca=26, find a^2+b^2+c^2

Answer 1

Step-by-step explanation:

(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(26)

81-52=a^2+b^2+c^2

29=a^2+b^2+c^2

hope it helps you.....