If the product of (x-a) (1 / 5 of x-a) does not contain an X term, then a is equal to?

If the product of (x-a) (1 / 5 of x-a) does not contain an X term, then a is equal to?

Original formula = x & # 178; - (a + 1 / 5) x + A / 5
If not, the coefficient is 0 '
So - (a + 1 / 5) = 0
a=-1/5