oh ok
\( 60 = (15\times10 \times sin \theta ) / 2\\ 120 = 150 \times sin \theta \\ \frac{12}{15} = sin \theta \\ 0.8= sin \theta \\ sin\theta = 0.8\\ first\;or \; second \;quadrant\\\)
asin(0.8) = 53.130102354156
\(\theta=(180n + (-1)^n*53)^\circ \qquad n\in Z\)