How to prove parallel lines using the converse triangle proportionality theorem

The video tutorial explains how to determine if two lines are parallel using the converse of the proportionality theorem. It involves setting up and solving proportions based on given measurements. The tutorial walks through the process of calculating and verifying proportions to prove parallelism, concluding with a successful demonstration of the theorem.

What theorem is used to determine if two lines are parallel by checking the proportionality of segments?

• Pythagorean Theorem

• Converse of the Proportionality Theorem

• Triangle Sum Theorem

• Alternate Interior Angles Theorem

If BC is 15 and BE is 6, what is the length of EC?

• 12

• 9

• 6

• 15

Which of the following proportions is set up to test for parallelism in the given problem?

• AD/BE = DC/EC

• BE/BC = DC/AD

• BC/BE = AD/DC

• BE/EC = AD/DC

What method is used to verify the equality of the proportions?

• Division

• Substitution

• Cross Multiplication

• Addition

What is the simplified form of the proportion 8/12?

• 1/2

• 2/3

• 3/4

• 4/5