Is it A ?f2001290 wrote:If xyz ≠ 0, is x (y + z) = 0?
(1) ¦y + z¦ = ¦y¦ + ¦z¦
(2) ¦x + y¦ = ¦x¦ + ¦y¦
1 - y and z are either both positive or both negative. In anycase, y+z not
equal to zero and we already know x not eq 0. So, product cannot be
equal to zero. Sufficient.
2 - no idea about the value of z. if z = -y, then we could get 0.
