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# Trig watch

1. So I’ve got a question and I’ve been given one side, the angle and the area of an irregular triangle. How do I rearrange 1/2absin(c) to find a missing side. I’ve looked online and I don’t know if I’ve been searching the wrong things but I can’t find it and would appreciate if anyone could help.
2. (Original post by Shaijohnson)
So I’ve got a question and I’ve been given one side, the angle and the area of an irregular triangle. How do I rearrange 1/2absin(c) to find a missing side. I’ve looked online and I don’t know if I’ve been searching the wrong things but I can’t find it and would appreciate if anyone could help.
If you have A, a and C and

then the missing side b is calculated by rearranging the formula such that b is the subject of the formula, that is,

.
3. Do you have a picture of the question?
4. (Original post by Shaijohnson)
So I’ve got a question and I’ve been given one side, the angle and the area of an irregular triangle. How do I rearrange 1/2absin(c) to find a missing side. I’ve looked online and I don’t know if I’ve been searching the wrong things but I can’t find it and would appreciate if anyone could help.
5. (Original post by Shaijohnson)
Use Area=1/2xb sinC

and rearrange to find x
6. Thank you
7. (Uploaded in two parts for some reason?) The question I’m asking is how to rearrange to find a missing side
8. Ok so we know:
1/2xbSinC=36.7
Multiply through by 2 to eliminate the 1/2
Which gives us xbSinC=73.4
Put in our values so x*13.8*Sin(45)=73.4
Divide both sides by 13.8 to get
Spoiler:
Show
367/69

Now divide both sides by sin(45) to get x on its own
Spoiler:
Show
x=7.5(1.d.p)

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