Question

FInd the measure of angle C

Answer 1

I've tried it twice and the second time i got 12.51400

Answer 2

I have fone \[a^2=13^2+17^2-2(13)(17)\cos47\]

Answer 3

done*

Answer 4

For this one, use the sine law. Do you know it?

Answer 5

@ospreytriple yeah hold on let me try it out

Answer 6

@ospreytriple 10sinB=17sin47???

Answer 7

Shouldn't it be 13, not 10?

Answer 8

@ospreytriple oh yeah sorry about that 13sinb=17sin4

Answer 9

OK. The way I'm used to using the sine law is as follows:\[\frac{ \sin \left( A \right) }{ a } =\frac{ \sin \left( B \right) }{ b }\]. Is this the way you have it?

Answer 10

@ospreytriple yeah i did that but you have to rearange to the way i had it and then do s\[sinb=\frac{ 17\sin47 }{ 13 }\]

Answer 11

I think there's an error in the rearranging. You have \[\frac{ \sin \left( B \right) }{ b }=\frac{ \sin \left( C \right) }{ c }\]To isolate sin(C) you would multiply both sides of the equation by c, giving\[\frac{ c \sin \left( B \right) }{ b }=\sin \left( C \right)\]Make sense?

Answer 12

@ospreytriple yeah

Answer 13

OK. So solve\[\sin \left( C \right)=\frac{ 17 \sin \left( 47 \right) }{ 13 }\]

Answer 14

@ospreytriple calculator got 1.27436702

Answer 15

What do you get for sin(47)?

Answer 16

@ospreytriple 0.7313

Answer 17

Good. Multiply that number by 17 and divide that answer by 13. What do you get?

Answer 18

@ospreytriple 0.956315

Answer 19

Excellent. Now evaluate \[C=\sin ^{-1}\left( 0.956315 \right)\]

Answer 20

@ospreytriple calculator is getting 73.00200763 but doesnt seem right at all

Answer 21

That's what I get. Is that one of your choices?

Answer 22

@ospreytriple oh nvm it is i was looking at the wrong problem lmao thank you!!

Answer 23

Yayyy! Just remember to be very careful how you use your calculator.