©G Dear2008 – Not to be sold/Free to use Similarity Rule 02 Stage 4 - Year 9 Press Ctrl-A ©G Dear2008 – Not to be sold/Free to use

We only need to show two, why? Similar Triangles 2 If 3 angles of one triangle are equal to 3 angles of another triangle, the 2 triangles are similar. We only need to show two, why? A All angles of triangle A are equal to all angles in triangle B. B They are similar

All angles of triangle A are equal to all angles in triangle B. Similar Triangles 2 If 3 angles of one triangle are equal to 3 angles of another triangle, the 2 triangles are similar. 60o 60o A 30o B All angles of triangle A are equal to all angles in triangle B. 30o They are similar

Formal Solution 2  ΔABC ||| ΔDEF Label each triangle. If 3 angles of one triangle are equal to 3 angles of another triangle, the 2 triangles are similar. A A = D B 30o 60o C 30o 60o B = E D C = F Label each triangle.  ΔABC ||| ΔDEF (equiangular) E F