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What is the length of cd in the diagram

What is the length of cd in the diagram-example-1
User Shenkwen
by
6.5k points

2 Answers

4 votes

Answer:

It is 5

Explanation:

User Mayur Kulkarni
by
7.1k points
4 votes

Answer:

5

Explanation:

Since the triangles are similar

The ratios have to be the same

AC BC

---------- = -------------

CE CD

21 20-x

--------- = -----------

7 x

Using cross products

21x = 7(20-x)

Distribute

21x = 140-7x

Add 7x to each side

21x+7x = 140-7x+7x

28x = 140

Divide each side by 28

28x/28 = 140/28

x =5

We want the length of CD

CD = x= 5

User Tameem Safi
by
6.9k points