Simplify. Assume x and y are nonnegative.

[tex]9\sqrt{56x^7y^{12}}=\\\\9\sqrt{4x^6\cdot14x \cdot (y^6)^2}=\\\\9y^6\sqrt{14x\cdot (2x^3)^2}=\\\\9y^6\cdot 2x^3\sqrt{14x}=\\\\18x^3y^6\sqrt{14x}[/tex]
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I actually answered first, but someone else copied me and reported me unfairly. I’ve typed in the step by steps.
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