highschoolmom2010 3 years ago a right triangle ABC, C is the right angle and CD is the altitude drawn to the hypotenuse. If AD =3 and BD=9 what is AC? show work

1. highschoolmom2010

thats as far as i got

2. ganeshie8

you may use geometric mean thingy to solve this or similiar triangles

3. highschoolmom2010

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4. ganeshie8

pick one

5. highschoolmom2010

geometric mean bc im not really good at it

6. ganeshie8

okay ! memorize this :- AC is the geometric mean of AD and AB AC = geometric mean of 3 and 12

7. ganeshie8

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8. highschoolmom2010

$\sqrt{12*3}=\sqrt{36}=6$ like this

9. ganeshie8

yes !

10. highschoolmom2010

just refreshing on the work we did like a week or so ago

11. ganeshie8

here is the rule :- Each leg of a right triangle is the 'geometric mean' between the hypotenuse(12) and the segment of hypotenuse adjacent to the given leg(3)

12. ganeshie8

lol i was on vacation for 2 weeks. and i remember we doing these back then.. .

13. highschoolmom2010

yea thx @ganeshie8 :D

14. ganeshie8

np :)