Question

please answer this please

Answer 1

(a+b+c)² = a²+b²+ c²+2ab+2bc + 2ca

(0)² = 16 + 2(ab+bc+ca)

0 = 16+2(ab+bc+ca)

-16 = 2(ab+bc+ca)

-16/2 => ab+ bc + ca

-8 = ab +bc +ca

hope it helps you.