Question

If a+b+c=9 and ab+BC+can=26 find a2+ b2+c2

Answer 1

Answer:

29

Step-by-step explanation:

formula is

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

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

that means substitute a+b+c=9,

                                    ab+bc+ca=26

then a^2+b^2+c^2=?

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

(9)^2=a^2+b^2+c^2+2(26)

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

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

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