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consider a triangle where a=80 degrees,a=2 cm and b=4 cm . how many possible triangles have the above properties

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0 You have a triangle with an angle of 80 degrees and the opposite side being 2 cm. You also have an adjacent side that's 4 cm long. Those sides and the angle specified make for an impossible situation. Let's prove that using the law of sines. The law of sines states that in a triangle, the ratio of the sine of an angle to the length of the opposite side is a constant within that triangle. So sin(A)/a = sin(B)/b = sin(C)/c Let's just deal with those sides and angles involving A and B. sin(A)/a = sin(B)/b Now substitute the known values sin(80)/2 = sin(B)/4 0.984807753/2 = sin(B)/4 0.492403877 = sin(B)/4 4*0.492403877 = 4*sin(B)/4 1.969615506 = sin(B) And we now have an impossible situation since the sine of an angle has to be in the range -1 to 1 and the value 1.969615506 is obviously well beyond that range. Therefore there are no triangles with that angle and side lengths.
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