Can't tension Belt - Pictures included

I have a maytag dryer that I cant seem to tension the belt… The belt arm in its normal resting position leaves a few inches of slack. That is the first picture.

In the second picture I pushed the belt arm further to the right so it hooked the motor bracket. I thought maybe this was the right place for it… but in this case the belt is too short.

any ideas what I am doing wrong?