Question

if x+y+z=0, then (x+y) (y+z) (z+x) is equal to which of the following​

Answer 1

The given condition gives three conditions.

• x+y=-z
• y+z=-x
• z+x=-y

If we substitute into the brackets we have multiplication of -x, -y, -z

The multiplication is -xyz.

Hope you understand.