A triangle has sides A, B, and C. The angle between sides A and B is pi/4π4. If side C has a length of 1 1 and the angle between sides B and C is pi/12π12, what is the length of side A?

1 Answer
Jul 22, 2017

The length of the side a=0.37a=0.37

Explanation:

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The angles are

hatC=1/4piˆC=14π

hatA=1/12piˆA=112π

hatB=pi-(1/4pi+1/12pi)=pi-(3/12pi+1/12pi)=8/12pi=2/3piˆB=π(14π+112π)=π(312π+112π)=812π=23π

The side c=1c=1

We apply the sine rule to the triangle

a/sin hatA=b/sin hatB=c/sin hatCasinˆA=bsinˆB=csinˆC

a/sin (1/12pi)=b/sin (2/3pi)=1/sin (1/4pi)asin(112π)=bsin(23π)=1sin(14π)

Therefore,

a=sin(1/12pi)/sin(1/4pi)=0.37a=sin(112π)sin(14π)=0.37

b=sin(2/3pi)/sin(1/4pi)=1.22b=sin(23π)sin(14π)=1.22