Q. In △FGH,g=170cm,f=960cm and ∠F=19∘. Find all possible values of ∠G, to the nearest 10th of a degree.Answer:
Apply Law of Sines: To find the possible values of /_G, 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 opposite angle is the same for all sides and angles in the triangle. The formula is:sin(A)a=sin(B)b=sin(C)cHere, we have side g opposite /_G, side f opposite /_F, and we are given the values of g, f, and /_F.
Write Formula with Given Values: First, let's write the Law of Sines formula using the given values:sin(F)f=sin(G)gsin(19°)960=sin(G)170
Solve for sin(G): Now, we solve for sin(G):sin(G)=960170⋅sin(19°)
Calculate sin(G) Value: We calculate the value of sin(G) using a calculator:sin(G)≈960170⋅0.32557sin(G)≈96055.3469sin(G)≈0.05765
Find Angle G: Next, we find the angle G by taking the inverse sine (arcsin) of sin(G):G≈arcsin(0.05765)
Check Validity of Second Value: Using a calculator, we find:G≈3.3°However, since the sine function is positive in both the first and second quadrants, there could be another possible value for angle G in the second quadrant. This value would be:G′=180°−GG′=180°−3.3°G′≈176.7°
Check Validity of Second Value: Using a calculator, we find:G≈3.3°However, since the sine function is positive in both the first and second quadrants, there could be another possible value for angle G in the second quadrant. This value would be:G′=180°−GG′=180°−3.3°G′≈176.7°We must check if the second possible value for angle G is valid by ensuring the sum of the angles in the triangle does not exceed 180°. Since we already have /_F = 19°, we add this to our two possible values for /_G:19°+3.3°+G′′≤180°19°+176.7°+G′′≤180°The first equation is valid for any angle G'', but the second equation is not possible because 19° + 176.7° already exceeds 180°. Therefore, the only possible value for /_G is 3.3°.
More problems from Find trigonometric functions using a calculator