A community for students.
Here's the question you clicked on:
 0 viewing
briana.img
 one year ago
Find the value of a .
briana.img
 one year ago
Find the value of a .

This Question is Closed

briana.img
 one year ago
Best ResponseYou've already chosen the best response.0I seriously just did a problem like this but I always forgot on how to use it

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3looks like a law of cosines problem?

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3hmm i think you need cosines for this you do not know any angle opposite one of the known sides

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0right you are. Cosine law required.

briana.img
 one year ago
Best ResponseYou've already chosen the best response.0\[\frac{ \sin52 }{ ? } = \frac{ sinb }{ 4 }\]

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3\[a^2=b^2+c^22bc\cos(A)\] \[a^2=4^2+7^22\times 4\times \cos(52^\circ)\] and a calcullator

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3if you want to use the law of sines (which you do , because it is easiest) you need 3 out of the for numbers to make a ratio

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3you do not have three out of any four, because you do not know the angle opposite any known side

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3you can see you ran in to that problem when you wrote \[\frac{ \sin52 }{ ? } = \frac{ \sin(b) }{ 4 }\]

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3you got only two of the four numbers, two are unknown so you must use the law of cosines for this one

briana.img
 one year ago
Best ResponseYou've already chosen the best response.0@misty1212 i got 5.52507014 from doing your way after square rooting

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3i can check if you like, i didn't do it

briana.img
 one year ago
Best ResponseYou've already chosen the best response.0@misty1212 i think it's right but can you check it please

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3http://www.wolframalpha.com/input/?i=sqrt%284%5E2%2B7%5E22*4*7*cos%2852%29%29

misty1212
 one year ago
Best ResponseYou've already chosen the best response.35.52 rounded looks good

briana.img
 one year ago
Best ResponseYou've already chosen the best response.0@misty1212 could you help me with another problem? please

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3or in your case 5.5 cause they rounded to one decimal place

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3yeah but i can't read what they are trying to find the value of in this case you know two angles so you know all three and therefore you can use the law of sines

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3what do they want, \(r\) ?

briana.img
 one year ago
Best ResponseYou've already chosen the best response.0@misty1212 trying to find the value of r which is reallyw eird

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3ok what is the measure of the angle opposite \(r\)?

briana.img
 one year ago
Best ResponseYou've already chosen the best response.0@misty1212 there's no angle opposite of r that's the weird part

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3of course there is lol

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3it is labelled \(\huge R\)

briana.img
 one year ago
Best ResponseYou've already chosen the best response.0@misty1212 there isn't!!

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3oh i see, you mean you don't know what it is

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3lets find it total in the triangle is 180 so it is \[1804563=72\]

briana.img
 one year ago
Best ResponseYou've already chosen the best response.0@misty1212 oooh yeah lmao forgot you could do it like that

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3now law of sines finishes it right?

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3\[\frac{r}{\sin(72)}=\frac{22}{\sin(45)}\] etc

briana.img
 one year ago
Best ResponseYou've already chosen the best response.0@misty1212 so it's rearrange to 22sin72=rsin45?

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3this time i notice they round to two places http://www.wolframalpha.com/input/?i=22sin%2872%29%2Fsin%2845%29

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3that step is not necessary

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3\[\frac{r}{\sin(72)}=\frac{22}{\sin(45)}\iff r=22\times\frac{ \sin(72)}{\sin(45)}\]

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3i know some math teacher might have said "cross multiply" but they are silly \[\frac{x}{a}=\frac{b}{c}\iff x=\frac{ab}{c}\]

briana.img
 one year ago
Best ResponseYou've already chosen the best response.0@misty1212 r=29.58993453?

briana.img
 one year ago
Best ResponseYou've already chosen the best response.0@misty1212 thank you!!! you really helped me tonight htis lesson really got me messed up

misty1212
 one year ago
Best ResponseYou've already chosen the best response.3you're welcome!\[\huge \color\magenta\heartsuit\]
Ask your own question
Sign UpFind more explanations on OpenStudy
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.