20:21 Triangle Proportionality Theorems

Front

What is the Triangle Proportionality Theorem?

Back

If a line is drawn parallel to one side of a triangle, it divides the other two sides proportionally.

Front

What does it mean for two figures to be similar?

Back

Two figures are similar if they have the same shape but not necessarily the same size.

Front

What is the relationship between corresponding angles in similar triangles?

Back

Corresponding angles in similar triangles are equal.

Front

What is the relationship between corresponding sides in similar triangles?

Back

Corresponding sides in similar triangles are proportional.

Front

If AB / BM = AC / CD, what does this represent?

Back

This represents a proportion between segments of a triangle divided by a line parallel to one of its sides.

Front

What is the significance of the 20:21 ratio in triangle proportionality?

Back

It indicates the proportional relationship between the segments created by a line intersecting two sides of a triangle.

Front

How do you find the missing length in a proportion?

Back

Cross-multiply and solve for the unknown length.

Front

What is an example of a proportion involving triangle segments?

Back

If AB / BM = AC / CD, and AB = 8, BM = 4, find AC.

Front

What is the formula for finding the length of a side in similar triangles?

Back

If triangles are similar, then the ratio of corresponding sides is equal to the ratio of their perimeters.

Front

What is the converse of the Triangle Proportionality Theorem?

Back

If a line divides two sides of a triangle proportionally, then it is parallel to the third side.