$\text{a)}5x^2-30xy=5x\left(x-6y\right)$  

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$\text{b)}9x{y}^2+3x^{2}y=3xy\left(3y+x\right)$  

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$\text{c)}48p^{3}r-36p{r}^2+24pr=12pr\left(4p^2-3r+2\right)$  

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$\text{d)}14m^{2}n-21m{n}^2+70mn=7mn\left(2m-3n+10\right)$