Question

In triangle ABC segment BD is an altitude. What is the length in units of BD?
A. 5 square root 6
B. 5
c. 6 square root 5
d. 9

http://tinypic.com/view.php?pic=fcsmly&s=6

Answer 1

BD is the geometric mean of 12 and 15....

BD splits up the right triagle into two similar triangles so you can use this proportion to solve for BD:
\[\huge \frac{12}{BD}=\frac{BD}{15} \]

Answer 2

I got 180

Answer 3

That's not an answer choice

Answer 4

cross multiply you have \(\large (BD)^2=12\cdot 15 \)
solve for BD...

Answer 5

oh so it's d?

Answer 6

can some1 tell me if it is?

Answer 7

how did you get d? (i'm not saying it's right or wrong)

Answer 8

pls explain....

Answer 9

I just don't know what it is because I crossed multiplied and got 180

Answer 10

but BD \(\ne \)180...
it's \(\large (BD)^2=180 \)

Answer 11

solve for BD....