 Page Three Practice Fill in your answer(s) in the box(es) provided. When you're all done, check your answer by holding your mouse cursor over the grey square below each diagram. 
1. Are these triangles congruent? Why of why not?  
2. Why are these triangles congruent? How long is side YF? 
3. Sometimes the problem has information missing that you have to provide yourself, based on geometry facts you have learned. There are some equal angles in the diagram. Check here if you don't know which ones. Then come back. These are triangles
Here is the diagram with the equal angles filled in. Why are the triangles congruent? See why here 
4. Prove that Δ ABC ≅ Δ CDA We have to prove the triangles are congruent using one of the shortcuts. Let's start by finding some equal things. Review parallel lines first; then come back. The parallel lines AB and CD mean that alternate angles ∠BAC and ∠DCA are equal ('Z' pattern) The line AC is common to both triangles, so this side is equal in both triangles. What shortcut proves the triangles are congruent? See the solution here. |