# Calculus Vs Straight lines

Calculus Level 4

Find the acute angle between the 2 lines passing through the origin and satisfying the differential equation, $$(4x-3y)dx+(2y-3x)dy=0$$.

If the answer can be represented as $$\arctan \left(\frac{a}{b}\right)$$ where $$a$$ and $$b$$ are co-prime.
Input your answer as $$a+b$$. Note: $$\arctan x$$ is an inverse trigonometric function.

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