Question

EXPANSIONS:
........................

Answer 1

(a+b+c)^2=a^2+b^2+c^2+2ab+2bc+2ca
12^2 = 50+2(ab+bc+ca)
144-50=2(ab+bc+ca)
ab+bc+ca=94/2=47

Answer 2

see if u can get that....and tell me if u have any doubt