Question

Find the value of r.

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Answer 1

have you covered the Law of Cosines yet?

Answer 2

Yes but i'm not very good at putting the formula together.

Answer 3

so... well.. any ideas on what angle R is?

Answer 4

Select one:
a. 16.36
b. 29.59
c. 38.14
d. 28.67

Its multiple choice.

Answer 5

I'd say either b or d

Answer 6

hmm ok... what do you based that on?

Answer 7

Ummmm

63+45=108 180-108=72

72 degrees makes R the largest angle and r is opposite of R so it couldn't be answer a soooo that would be why.

Answer 8

@zepdrix

Answer 9

Do you know how to solve this?

Answer 10

ok.... so we know that R is 72 degrees... so

actually we could just use the Law of sines.... will be simpler

Answer 11

\(\bf \cfrac{sin(P)}{p}=\cfrac{sin(R)}{r}\implies r=\cfrac{p\cdot sin(R)}{sin(P)}\implies r=\cfrac{22\cdot sin(72^o)}{sin(45^o)}\)

Answer 12

I got 29.6

Answer 13

So b.

Answer 14

29.5899345264 so yeap

Answer 15

Thanks.

Answer 16

yw