How to calculate the sides of a triangle when only the area and 2 angles are given?

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I'm reading the book 'Trig without tears' by Stan Brown and there is a table mentioning the method for finding the sides of a triangle (not only right triangles) when only the area and 2 angles are given. It wrote

'Find the third angle. Area = ½a b sin C, half of base × height, so substitute b = a×sin B/sin A from the Law of Sines (equation 28) and solve for a = √[2 Area × sin A / sin B sin C]. Then use the Law of Sines twice more to find the other two sides.'

I really can't understand it. Can anyone help me please?? Thanks!!!! :)

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1 Answer

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$$b = a * {\sin B \over \sin A}$$

So, $$Area = 1/2 * a^2 * {\sin B * \sin C \over \sin A}$$

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