Garmin GPS 175 Pilot's Manual page 93

Delete any existing flight plan before attempting to graphically edit a direct-to
waypoint. Map does not allow the addition of an intermediate waypoint
between the current position and a direct-to waypoint unless the waypoint is in
the flight plan.
190-02207-02 Rev. B GPS 175/GNX 375 Pilot's Guide
3. Tap and drag the leg to a
new waypoint or airway,
then release.
The temporary flight plan
adjusts to show the new route.
If no other edits are necessary,
tap Done.
The new waypoint now appears
in the active flight plan.
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