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Trigonometry Question - Area of a Triangle Watch

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    In the triangle XYZ, XY = 4.6 cm and YZ = 6.9 cm. The area of the triangle is 7.3cm^2. Find two possible values for ∠XYZ.

    I've figured out one possible angle using the formula for the area of a triangle (27.4° ) but don't quite know how to get a second solution.

    I'd be really grateful for some tips!

    Thanks!
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    (Original post by grace15)
    In the triangle XYZ, XY = 4.6 cm and YZ = 6.9 cm. The area of the triangle is 7.3cm^2. Find two possible values for ∠XYZ.

    I've figured out one possible angle using the formula for the area of a triangle (27.4° ) but don't quite know how to get a second solution.

    I'd be really grateful for some tips!

    Thanks!
    Without seeing your working, I presume you got to the stage where you had sin x = something, and then just found the inverse sine.

    Note that sin x = sin (180 - x).

    The sine graph is symmetrical about x= 90.

    So if x is a solution to sin x = something, then 180-x is another solution.
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    Thank you so much!

    (Original post by ghostwalker)
    Without seeing your working, I presume you got to the stage where you had sin x = something, and then just found the inverse sine.

    Note that sin x = sin (180 - x).

    The sine graph is symmetrical about x= 90.

    So if x is a solution to sin x = something, then 180-x is another solution.
 
 
 
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