25sin@ -1.5 cos@ = 20 @ = theta
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Originally Posted by jewd777 25 sin@ -1.5 cos@ = 20, whats @ = ? Hint: Apply the identity $\displaystyle A\cos\theta+B\sin\theta=\sqrt{A^2+B^2}\cos\!\left( x-\tan^{-1}\!\left(\tfrac{B}{A}\right)\right)$
there may be a more clever way but by brute force and ignorance: Solve for 25 sin(@) = 20+1.5cos(@) square both sides and convert the LHS to a fn of cos(@) you now have a quadratic in cos@
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