Physics resultant forces question

Hi I was wondering if someone could please explain the answer to the following question for me:

The forces acting on the ladder are in equilibrium.
Draw an arrow on Figure 7 to show the direction of the resultant force from the ground acting on the ladder. Label your arrow G

The markscheme states: arrow drawn upwards from point of contact with ground
between ladder and vertical which when extended would pass through ‘on ladder’ part of label

and the examiner report clarifies that the arrow for force G, if extended, would go through the point where the weight and the resultant force from the wall, when extended, would intersect (in other words just under the word ladder

I understand why the force acts at an angle to the right, however I don't understand why it acts specifically at this angle, so would really appreciate if someone could please explain this for me.
Thank you very much in advance!