Question

I solved the problem can someone check to see if I did it right? Medal award

To find a distance across a small lake, a surveyor has taken the measurements shown. Find the distance across the lake, AB

Answer 1

I multiplied sin 40.3 (3.56) then I multiplied both sides by 3.56 to illuminate the x by itself I got x=2.302571615

Answer 2

Tottaly not stalking iron man

Answer 3

Welcome to openstudy ;D

*watches iron man*

Answer 4

lol )

Answer 5

I made him log off x'D

Answer 6

sorry about that x'D

Answer 7

what are you talking about :D

Answer 8

abhisar was iron man :D

Answer 9

i was watching him :D

Answer 10

If i may, you should bump this question now so people see it again LOL

Answer 11

lol ok )

Answer 12

Im hulk... *farts rainbows and flys away*

Answer 13

omg XD

Answer 14

How do you like openstudy so far? :P

Answer 15

:D

Answer 16

I dont know what that means :D

Im the wierd ambassador... have you noticed? here @satellite73 help this guy LOL

Answer 17

mhm )

Answer 18

satallite didnt show up yet

Answer 19

@amistre64 Help dis guy -_-

Answer 20

lots of spam in this post ... whats the question?

Answer 21

use law of cosines ...

Answer 22

Welp... sorry for the spam LOL

Answer 23

but is it right? The way I solved the problem?

Answer 24

no, its not, you assumed a right triangle, but its not a right triangle

Answer 25

\[c^2=a^2+b^2-2ab~\cos(\alpha)\]

Answer 26

how do I know what to put in for the c^2 if i'm only given side length 2.82 and 3.56?

Answer 27

the value of c is what you are trying to find ... its not something you "put in" its something you get as a result.

Answer 28

if you have 2 sides and the angle between them, then you have all you need to calculate the missing side.

Answer 29

so I substitute the 2.82 as the a and the 3.56 as the b into the equation. We are solving for c?

Answer 30

yes, and the angle is subbed into the cosine part

then sqrt to solve for c

Answer 31

Rainbows

Answer 32

amistre64, so would you set it up as c^2=(2.82)^2+(3.56)^2-2(2.82)(3.56)Cos c

Answer 33

yes, but the last little bit is off

\[ c^2=(2.82)^2+(3.56)^2-2(2.82)(3.56)\cos\color{red}{40.3} \]

Answer 34

http://www.wolframalpha.com/input/?i=sqrt%28%282.82%29%5E2%2B%283.56%29%5E2-2%282.82%29%283.56%29cos%2840.3%29%29&a=TrigRD_D

Answer 35

2.30496 would be the distance across the lake ab

Answer 36

yes, rounded to whatever decimation you like

Answer 37

ok thanks so much!

Answer 38

youre welcome