Answer:
5. -18x^3y^4 +54x^2y^4
6. 6x^2 -40x +50
Step-by-step explanation:
Use the distributive property. The factor outside parentheses multiplies each term inside parentheses.
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[tex](9xy)(-2x^2y^3+6xy)=(9xy)(-2x^2y^3)+(9xy)(6xy^3)\\\\=\boxed{-18x^3y^4+54x^2y^4}[/tex]
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[tex](3x-5)(2x-10)=3x(2x-10)-5(2x-10)\\\\=6x^2-30x-10x+50=\boxed{6x^2-40x+50}[/tex]