contestada

BC¯¯¯¯¯ is parallel to DE¯¯¯¯¯. What is AB? Enter your answer in the box. units An upside down triangle with vertices labeled as A, D, and E. Side D E is the base and the bottom vertex is A. Sides A D and A E contain midpoints B and C, respectively. A line segment is drawn from B to C parallel to the base. Segment B D is labeled as 17. Segment A C is labeled as 42. Segment C E is labeled as 21.

Respuesta :

TheOneandOnly003

I believe the answer is 34.

Answer:

34

Step-by-step explanation:

The ratio of AB to BD will be the same as the ratio of AC to CE.

The ratio of AC to CE is 42/21.

AB is unknown.  Using the variable x to represent AB, we have the ratio x/17.

This gives us the proportion

42/21 = x/17

Cross multiplying, we have

42(17) = 21(x)

714 = 21x

Dividing both sides by 21,

714/21 = 21x/21

34 = x