# Slope from similar triangles

What do similar triangles have to do with the slope of a line?

## Small Triangle

1. What are the coordinates of point A? 2. What are the coordinates of point C? 3. What are the coordinates of point D? 4. Use these coordinates to find the slope of segment AD. What is the slope?

## Large Triangle

1. What are the coordinates of point D? 2. What are the coordinates of point E? 3. What are the coordinates of point F? 4. Use these coordinates to find the slope of segment DF. What is the slope?

## Both Triangles

1. Are these triangles similar? 2. Did you use the information from all of the points? Why or why not? 3. If you did not have a graph with a line on it, but you were given two similar triangles such as these, could you find the slope of their hypotenuse?