Answer:
7. one triangle
8. two triangles
Step-by-step explanation:
When you are given two sides and one of the opposite angles, you can make a determination as follows:
- If the given angle is opposite the longest given side, there is one solution.
- If the given angle is opposite the shortest given side, there may be 0, 1, or 2 solutions.
For the latter case, the possibilities for sides b, c, and angle C are ...
C > 90° . . . . . . . . no solution
(b/c)sin(C) > 1 . . . no solution
(b/c)sin(C) = 1 . . . 1 solution
(b/c)sin(C) < 1 . . . 2 solutions
(The expression (b/c)sin(C) gives sin(B), so the value must lie within the range of the sine function in order for there to be any solution.)
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7. The given angle is opposite the longest given side. There is one solution.
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8. The given angle is opposite the shortest given side, so we compute
(b/c)sin(C) = (34/28)sin(20°) ≈ 0.41
This is less than 1, so there are two solutions.
