Question

What is the length of QR to the nearest hundredth of a centimeter? _____cm

Answer 1

You're gonna want to use the law of sines. Should we go over that again? :)

Answer 2

yes please

Answer 3

So the sin of an angle over the opposite length is going to be equal to the sin of any other angle over the length. So in this problem we have a length of 12.38 opposite to a sin of 90. That is going to be equal to the length of QR over sin 49. The equation would look like this\[\frac{ 12.38 }{ \sin(90) }=\frac{ x }{ \sin(49) }\] Now all you have to do is get x alone.

Answer 4

sin(49)(12.38) = sin(90)x
606.62 = 90x
x = 6.74

Answer 5

is that right? o.o

Answer 6

Well sin(90) is always equal to 1. So 12.38/sin(90) = 12.38. So just multiply 12.38 by sin(49) to get 9.34.

Answer 7

I see

Answer 8

You get x alone by doing\[\frac{ 12.38 }{ \sin(90) }=\frac{ x }{ \sin(49) }\to \sin(49)*\frac{ 12.38 }{ \sin(90) }=x\]

Answer 9

I forgot to find out what sin(90) and sin(49) equals because I didn't use the right calculator and thought I could just cancel it out.

Answer 10

sin(90)=1 and sin(49)=.754

Answer 11

kk Thanks~

Answer 12

No problem :)