Two corners of a triangle have angles of (7 pi ) / 12 7π12 and pi / 6 π6. If one side of the triangle has a length of 6 6, what is the longest possible perimeter of the triangle?

1 Answer
Jul 8, 2017

THe longest perimeter is =26.1u=26.1u

Explanation:

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Let

hatA=7/12piˆA=712π

hatB=1/6piˆB=16π

So,

hatC=pi-(7/12pi+1/6pi)=1/4piˆC=π(712π+16π)=14π

The smallest angle of the triangle is =1/6pi=16π

In order to get the longest perimeter, the side of length 66

is b=6b=6

We apply the sine rule to the triangle DeltaABC

a/sin hatA=c/sin hatC=b/sin hatB

a/sin (7/12pi) = c/ sin(1/4pi)=6/sin(1/6pi)=12

a=12*sin (7/12pi)=11.6

c=12*sin(1/4pi)=8.5

The perimeter of triangle DeltaABC is

P=a+b+c=11.6+6+8.5=26.1