Answer:
Explanation:
1)
Congruency shortcuts:
HL, SSS, SAS, ASA, and AAS
where S=side
A=angle
H=hypotenule
L=leg
HL is only for a right triangle
If you can prove sides and angles are congruent according to those 5 rules, you have proven the triangles are congruent
Similarity shortcuts:
AA, SAS, SSS
We have triangle similarity if (1) two pairs of angles are congruent (AA) (2) two pairs of sides are proportional and the included angles are congruent (SAS), or (3) if three pairs of sides are proportional (SSS)
2)
BG ≅ GD >Given from image
IG ≅ GO >Given from image
<BGI ≅ <DGO >Vertical Angles
ΔBGI ≅ ΔDGO >SAS
You have proven that the triangles are congruent because you used the shortcut by proving a side and angle and a side are congruent so SAS makes them congruent