.

[red snow]

Stress Diagram and Bow's Notation

[red snow]

The first way I notice is to use triangle dbc to find length bd via the pythagorean theorem.

[merry stream]

You wont even need pythag theorem. If we're allowed to assume that gd and cb are parallel we can say triangle bcd is a special 30-60 triangle. And if we can assume that 7root3/2 w is all of cb, ||then bd is just 7/2 w. ||
||7/2 w - w = 5/2 w||
||3w - 5/2 w = w/2||

I spoilered the solution so that way you can just use what i preface first and connect the dots

[merry stream]

Then i think i'm over my head in reading the diagram 😅

No as is i thought the stress diagram was all that was needed. It seems to be the answer key and the one in the top corner i cant make heads or tails of it 😅