Question

An archaeologist wants to find the height AB of a rock formation. She places a marker at C and measures the distance from C to B. Then she measures the same distance from C and places a marker at D. If DC = 4.2 m and DE = 10.5 m, what is AB (the height of the rock)?


A.
14.7 m

B.
4.2 m

C.
10.5 m

D.
6.3 m

Answer 1

oh no! a real life picture! D:

Answer 2

yea :o lol

Answer 3

figure http://prntscr.com/8rhvg0 and we are shown via diagram that CB is congruent to DC

Answer 4

k

Answer 5

now what ^-^

Answer 6

so proportion DE/DC=AB/CB becomes 10.5/4.2=x/4.2 well. it's really obvious now huh? lol

Answer 7

haha, b? i'd hope

Answer 8

:| no.\[\frac{DE}{DC}=\frac{AB}{CB}\rightarrow\frac{10.5}{4.2}=\frac{x}{4.2}\rightarrow10.5\times4.2=4.2x\rightarrow x=?\]

Answer 9

>.<

Answer 10

dammit

Answer 11

solve for x silly

Answer 12

a

Answer 13

lol

Answer 14

lol, no not the answer!

Answer 15

that's the reason i don't gamble :p got no luck

Answer 16

D right? haha

Answer 17

whhyyy are you guessing!! jeez !
figure hint http://prntscr.com/8rhygr

Answer 18

3/4 guess its c

Answer 19

xD

Answer 20

omg jeez. lol look: http://prntscr.com/8rhyyy we got ASA postulate here, means they're similar - then DE=AB=10.5m silly

Answer 21

yay

Answer 22

-facepalm- never helping you again!!

lol jk

Answer 23

lmao

Answer 24

thanks for the help