Question

If a^2+ b^2+c^2=20 and ab+bc+ca=8, find a+b+c. Plzz answer fast.​

Answer 1

Answer:

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

(a+b+c)^2=20+2(8)

(a+b+c)^2=36

a+b+c=√36

a+b+c,=6