Question

If a+b+c=6 and ab+bc+ca=15, then a2+b2+c2=

Answer 1

Answer:

36

Step-by-step explanation:

a2+b2+c2= (a+b+c)(a+b+c)

=6×6

=36

Answer 2

Answer:

6

Step-by-step explanation:

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

(6)^2 = a^2+b^2+c^2+2(15)

36 = a^2+b^2+c^2+ 30

36-30 = a^2+b^2+c^2

a^2+b^2+c^2 =6