If a, b, c are three real numbers such that a+b+c=0 (at least one a, b, c is not equal to zero) and az1+bz2+cz3=0, then z1,z2,z3 :
are collinear
form an equilateral triangle
form a scalene triangle
form a isosceles triangle
az1+bz2+cz3=0, a+b+c=0. at least one of a, b, c≠0 and a, b,c∈R . Let a≠0
Then z1=bz2+cz3b+c [∵ −a=b+c]
Thus, z1 divides the line segment joining z2 and z3 in the ratioc : b and therefore z1,z2,z3 are collinear