Why did Russia, Prussia, and Austria agree to partition Poland?

In 1730 the neighbors of the Polish–Lithuanian Commonwealth (Rzeczpospolita), namely Prussia, Austria and Russia, signed a secret agreement to maintain the status quo: specifically, to ensure that the Commonwealth laws would not change.

So basically they did it to ensure that the commonwealth laws would not change.

answer; (b) capitalism;

answer; i believe its called ; checks   and balances;