Answer:
see below
Explanation:
ASA congruence theorem: If two angles and the side between two angles of one triangle are congruent to the corresponding angles and side of another triangle, then the two triangles are congruent.
△ABG and △IBG has same side BG, ∠ABG congruent with ∠IBG, ∠AGB congruent with ∠IGB
Therefore △ABG is congruent with △IBG
then IG is congruent with AG