Question

2. Find the number of distinct triangles with c=11,b=7,B=18 a.0 b.1 c.2 d. cannot be determined

Answer 1

Answer: Choice C) 2

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Explanation:

Using the law of sines, we get
sin(B)/b = sin(C)/c
sin(18)/7 = sin(C)/11
0.0441452849107 = sin(C)/11
11*0.0441452849107 = sin(C)
0.4855981340177 = sin(C)
sin(C) = 0.4855981340177
C = arcsin(0.4855981340177) or C = 180-arcsin(0.4855981340177)
C = 29.0516679549861 or C = 150.948332045013
There are two possibilities for angle C because of something like sin(30) = sin(150) = 1/2 = 0.5

Those approximate values of C round to
C = 29.05 and C = 150.95

If C = 29.05, then angle A is
A = 180-B-C
A = 180-18-29.05
A = 132.95
Making this triangle possible since angle A is a positive number

If C = 150.95, then angle A is 
A = 180-B-C
A = 180-18-150.95
A = 11.05
making this triangle possible since angle A is a positive number

There are two distinct triangles that can be formed. 
One triangle is with the angles: A = 132.95, B = 18, C = 29.05
The other triangle is with the angles: A = 11.05, B = 18, C = 150.95
The decimal values are approximate