Determining parallel lines using the proportionality theorem of parallel lines

The video tutorial explains the triangle proportionality theorem, focusing on setting up and simplifying proportions to prove parallel lines. It involves calculating segment lengths and using ratios to demonstrate the theorem's application in geometry.

What is the primary goal when using the triangle proportionality theorem?

• To find the area of a triangle

• To determine the type of triangle

• To establish a proportion to prove lines are parallel

• To calculate the perimeter of a triangle

If AE is 30 and the total length is 45, what is the length of EC?

• 10

• 15

• 20

• 25

What is the relationship between AD and DB if AD is twice the length of DB?

• AD is three times the length of DB

• AD is twice the length of DB

• AD is equal to DB

• AD is half of DB

How can you verify that two lines are parallel using ratios?

• By checking if the sum of the ratios is zero

• By ensuring the ratios are equal

• By multiplying the ratios

• By subtracting the ratios

What is the simplified ratio if DB is 15 and AD is twice the length of DB?

• 3:1

• 2:1

• 4:1

• 1:1