Q. In △VWX,w=510 inches, v=890 inches and ∠V=137∘. Find all possible values of ∠W, to the nearest degree.Answer:
Apply Law of Sines: To find the possible values of /W, we can use the Law of Sines, which states that the ratio of the length of a side of a triangle to the sine of the angle opposite that side is the same for all three sides of the triangle. The formula is given by:sin(A)a=sin(B)b=sin(C)cwhere a, b, and c are the lengths of the sides, and A, B, and C are the angles opposite those sides, respectively. In our case, we have:sin(V)v=sin(W)wWe can plug in the values we know to find sin(W):sin(137°)890=sin(W)510
Find sin(137°): First, we need to find the value of sin(137°). Since 137° is in the second quadrant where sine is positive, we can use the fact that sin(180°−θ)=sin(θ) for angles in the second quadrant. Therefore, sin(137°)=sin(180°−137°)=sin(43°).
Calculate sin(W): Now we can solve for sin(W):sin(W)=510×sin(43°)/890We can use a calculator to find sin(43°) and then compute sin(W):sin(43°)≈0.682sin(W)≈510×0.682/890sin(W)≈0.390
Find angle W: Now that we have sin(W), we can find the angle W by taking the inverse sine (arcsin) of 0.390. However, we must consider that there could be two possible angles for W in a triangle since the sine function is positive in both the first and second quadrants. We will find the principal value (the smallest angle) first:W≈arcsin(0.390)W≈23∘ (to the nearest degree)
Consider Supplementary Angle: To find the second possible value for angle W, we need to consider the supplementary angle, since sin(W)=sin(180°−W). This is because in a triangle, the sum of the angles must be 180°, and we already have one angle that is 137°. The sum of the remaining two angles must be 180°−137°=43°. Since we found one possible value for W to be 23°, the other value must be 43°−23°=20°.
Consider Supplementary Angle: To find the second possible value for angle W, we need to consider the supplementary angle, since sin(W)=sin(180°−W). This is because in a triangle, the sum of the angles must be 180°, and we already have one angle that is 137°. The sum of the remaining two angles must be 180°−137°=43°. Since we found one possible value for W to be 23°, the other value must be 43°−23°=20°.However, upon reviewing the last step, we realize that the second angle calculation was incorrect. Since we already have one angle of 137°, and we found W to be 23°, the third angle (angle sin(W)=sin(180°−W)1) would be sin(W)=sin(180°−W)2. This means that there is only one possible value for angle W, which is 23°, because the angles in a triangle must sum up to 180°, and having two different values for angle W would violate this rule. Therefore, the only possible value for angle W is 23°.
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