Parallelogram - two sides

The parallelogram has the sides a = 25.3 b = 13.8, and the angle closed by the sides is a = 72°.
Calculate the area of the parallelogram.

Final Answer:

S =  332.0519

Step-by-step explanation:

$$\begin{gathered} a=25.3 \\ b=13.8 \\ \beta =72{}^{\circ } \\ \phi =180-\beta =180-72=108{}^{\circ } \\ h=b\cdot \sin \phi =b\cdot \sin 108°=13.8\cdot \sin 108°=13.8\cdot 0.951057=13.12458 \\ S=a\cdot h=25.3\cdot 13.1246=332.0519 \end{gathered}$$

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