How does pie/6 + pie(n)/3 equal the same as (2n+1)(pie/6)

here is how one person showed me:
pi/6 + npi/3

Simplifying,
pi/6 + 2npi/6 (multiplied second term by 2/2, or 1)

Equals, (2n +1)(pi/6), combining like terms.

i don't get how you get from pi/6 + 2npi/6 to (2n+1)(pi/6)

can someone explain step by step how that happened?
my teacher won't give me credit if i just leave it at pi/6 + npi/3 /:
thanks so much! [:

pi/6 + 2npi/6

Take pi/6 common.

pi/6( 1 + 2n)
= (2n + 1)pi/6

pie/6 + pie(n)/3
= pie/6 + 2pie(n)/6
= (1+2n)(pie/6)
= (2n+1)(pie/6)