Quote: 11pi/4 answer cannot be in decimal form
there's really no way to simplify this.
Maybe what you mean is what angle is it congruent to. If so
remember that an angle alpha is congruent to all angles (alpha + 2pi * k) where k is any integer
we note
2pi < 11pi/4 < 4pi
so
11pi/4 - 2pi =
11pi/4 - 8pi/4 =
3pi/4
and thus 11pi/4 is congruent to 3pi/4
+6251 
