Question

The length of the shadow of a building is 100 meters, as shown below:

The shadow of a building is 100 meters long. The acute angle that the shadow makes with the line joining the tip of the building to the end of the shadow measures 45 degrees.

What is the height of the building?

Answer 1

@dan815 @jim_thompson5910 @zzr0ck3r @HS_CA

Answer 2

how far did you get?

Answer 3

not far

Answer 4

do you have an equation set up?

Answer 5

thats my problem

Answer 6

with respect to the 45 degree angle, we can add these labels

Answer 7

which trig function will we use?

Answer 8

tangent

Answer 9

yes since tan(angle) = opp/adj

Answer 10

so tan(45) = h/100

Answer 11

are you able to isolate h in `tan(45) = h/100` ?

Answer 12

no clue

Answer 13

it might help to evaluate tan(45) first

use this calculator

http://web2.0calc.com/

to find the value of `tan(45)` and tell me what that is

Answer 14

1

Answer 15

yep

Answer 16

so `tan(45) = h/100` is the same as `1 = h/100`

Answer 17

so h = ??

Answer 18

100

Answer 19

good

Answer 20

this is a 45-45-90 triangle with congruent legs

Answer 21

wait is that it? 100 is the answer?

Answer 22

thanks :D

Answer 23

yeah you multiply both sides of `1 = h/100` by 100 to isolate h, you'll find that h = 100