2139

Prove the red triangles are similar.

2135

Prove the red and blue triangles are similar.

2132

Prove the red and blue triangles are similar.

2103

The red points are the midpoints of the green chords. Prove the red and blue triangles are similar.

2039

The green triangle is a rotation of the blue triangle. Prove the red triangle is similar to both of them.

2033

Prove the red and blue triangles are similar.

2007

Prove the red triangles are similar.

1931

Prove the red and blue triangles are similar.

1837

Prove the blue and red triangles are similar.

1798

Prove the red and blue triangles are similar.

1768

Prove the red and blue triangles are similar.

1711

Green points are reflected about the sides of the blue triangle. Prove the red and blue triangles are similar.

1692

Prove the red triangles are similar.

1683

Green points are trisection points of altitudes of the blue triangle. Prove the red and blue triangles are similar.

1682

Green points are midpoints of altitudes of the blue triangle. Prove the red and blue triangles are similar.

1662

Prove the blue and red triangles are similar.

1629

The purple points are the midpoints of the sides of the yellow triangle. Prove the yellow and red triangles are similar.

1474

Prove the red triangles are similar.

1429

Prove the red triangles are similar.

1428

Prove the green triangles are similar to the red triangle.