If (a-b), a and (a+b) are zeros of the polynomial 2x³-6x²+5x-7, write the value of a?

If (a-b), a and (a+b) are zeros of the polynomial 2x³-6x²+5x-7, writ

1.	If (a-b), a and (a+b) are zeros of the polynomial 2x³-6x²+5x-7, write the value of a?
Answer» I think a=1.