<s>[INST] Pre calculus fraction simplify question Simplify:
$$\frac{\frac{16x^4}{81} - y^4}{\frac{2x}{3} + y}$$
Wolfram alpha confirms the answer from the answer sheet: Wolframalpha answer
 [/INST] $$\frac{\frac{16x^4}{81} - y^4}{\frac{2x}{3} + y}=\frac{16x^{4}-3^4y^4}{81}\cdot \frac{3}{2x+3y}=\frac{(4x^2-9y^2)(4x^2+9y^2)}{81}\cdot \frac{3}{2x+3y}=\frac{(2x-3y)(2x+3y)(4x^2+3y^2)}{81}\cdot \frac{3}{2x+3y}.$$
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