MATHEMATICS. LET a,b,c belongs toa set of real numbers.Suppose that there are real numbers x,y,z

Question

LET a,b,c belongs toa set of real numbers.Suppose that there are real numbers x,y,z not all zero such that x=cy+bz,y=az+cx,& z=bx+ay.Then a to the power whole square+b to the power whole square+c to the power whole squqre+2abc is = to
(1) 0 (2) 1 (3) 2 & (4) -1