## anonymous one year ago Fan & Medal Calculate the length of AD given AB = 7 cm, AC =15 cm, and AE = 20. 3.25 5.25 2.5 5.5 http://static.k12.com/eli/bb/817/-1/0/2_36869_44974/-1/5c45df68fdad740c9f94d22ea5f92dd60c7a03f7/media/da937563f2abb5ff3640096bcfa86f9197313378/mediaasset_651711_1.jpg

1. freckles

$\text{ AB } \cdot \text{ AC }=\text{ AE } \cdot \text{ AD }$

2. anonymous

7x15=20x?

3. freckles

yep solve for x aka AD

4. freckles

wait that one x over on the left hand side is a multiplication sign right?

5. anonymous

yes

6. freckles

$7 \cdot 15=20x \\ \text{ divide both sides by } 20$

7. anonymous

105/20=5.25

8. freckles

yes

9. anonymous

thanks.

10. freckles

np that is called the intersecting secant theorem